estimations of octanol solubility, vapor...

Estimations of Octanol Solubility, Vapor Pressure, Octanol-air Partition Coefficient, and Air-water Partition Coefficient

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Authors Sepassi, Kia

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ESTIMATIONS OF OCTANOL SOLUBILITY, VAPOR PRESSURE, OCTANOL-AIR

PARTITION COEFFICIENT, AND AIR-WATER PARTITION COEFFICIENT

By

Kia Sepassi

___________________________

Copyright © Kia Sepassi 2007

A Dissertation Submitted to the Faculty of the

DEPARTMENT OF PHARMACEUTICAL SCIENCES

In Partial Fulfillment of the Requirements

For the degree of

DOCTOR OF PHILOSOPHY

In the Graduate College

THE UNIVERSITY OF ARIZONA

2007

2

THE UNIVERSITY OF ARIZONAGRADUATE COLLEGE

As members of the Dissertation Committee, we certify that we have read the dissertation

prepared by Kia Sepassi

entitled Estimations of Octanol Solubility, Vapor Pressure, Octanol-air

Partition Coefficient, and Air-water Partition Coefficient

and recommend that it be accepted as fulfilling the dissertation requirement for the

Degree of Doctor of Philosophy

_______________________________________________________________________ Date: 01-23-2007Samuel H. Yalkowsky, Ph.D.

_______________________________________________________________________ Date: 01-23-2007Michael Mayersohn, Ph.D.

_______________________________________________________________________ Date: 01-23-2007Paul B. Myrdal, Ph.D.

_______________________________________________________________________ Date:

_______________________________________________________________________ Date:

Final approval and acceptance of this dissertation is contingent upon the candidate’ssubmission of the final copies of the dissertation to the Graduate College.

I hereby certify that I have read this dissertation prepared under my direction andrecommend that it be accepted as fulfilling the dissertation requirement.

________________________________________________ Date: 01-23-2007Dissertation Director: Samuel H. Yalkowsky, Ph.D.

3

STATEMENT BY AUTHOR

This dissertation has been submitted in partial fulfillment of requirements for an

advanced degree at The University of Arizona and is deposited in the University Library

to be made available to borrowers under rules of the Library.

Brief quotations from this dissertation are allowable without special permission, provided

that accurate acknowledgment of the source is made. Requests for permission for

extended quotation from or reproduction of this manuscript in whole or in part may be

granted by the copyright holder.

Kia Sepassi

4

ACKNOWLEDGEMENTS

I would like to express my sincere gratitude to my advisor and mentor Dr. Samuel

Yalkowsky for his guidance, commitment, and encouragement. I will always remember

and cherish my time spent discussing scientific matters and philosophic issues.

I would also like to thank my dissertation committee members, Dr. Michael Mayersohn

and Dr. Paul Myrdal, for their many countless hours of time and advice. I would also like

to express my gratitude to my minor committee members, Dr. Scott Saavedra and Dr.

James Farrell, for dedicating their time to serve on my committee.

I would also like to thank my many colleagues past and present at the The University of

Arizona, especially Dr. Marc Tesconi for teaching me the art of dedication.

Finally, I would like to thank my parents, sister, and brother for their love and continuous

support. This accomplishment belongs to us all, it is especially symbolic of the sacrifices

made by Mom and Dad.

5

DEDICATION

To My Parents

6

TABLE OF CONTENTS

LIST OF FIGURES ...........................................................................................................10

LIST OF TABLES .............................................................................................................11

ABSTRACT.......................................................................................................................12

CHAPTER 1: INTRODUCTION......................................................................................13

1.1 Overview............................................................................................................13

1.2 Aims of This Study ............................................................................................15

CHAPTER 2: MOLAR OCTANOL SOLUBILITY OF ORGANIC SOLUTES..............17

2.1 Introduction........................................................................................................17

2.2 Background........................................................................................................17

2.2.1 Regular Solution Theory................................................................................17

2.2.2 Scatchard-Hildebrand Activity Coefficient....................................................18

2.2.3 Miscibility of Liquid Solutes with Octanol ...................................................19

2.2.4 Ideal Crystalline Solubility ............................................................................22

2.2.5 Entropy of Melting.........................................................................................22

2.2.6 Molar Octanol Solubility ...............................................................................24

2.3 Experimental ......................................................................................................25

2.3.1 Miscibility Range...........................................................................................25

2.3.2 Molar Solubility .............................................................................................25

7

TABLE OF CONTENTS - CONTINUED

2.4 Results and Discussion ......................................................................................26

2.4.1 Miscibility Range...........................................................................................26

2.4.2 Molar Solubility .............................................................................................28

2.5 Conclusion .........................................................................................................30

CHAPTER 3: SATURATED VAPOR PRESSURE...........................................................31

3.1 Introduction........................................................................................................31

3.2 Background........................................................................................................32

3.2.1 Entropy of Melting.........................................................................................34

3.2.2 Entropy of Boiling .........................................................................................34

3.2.3 Heat Capacity Change on Melting .................................................................35

3.2.4 Heat Capacity Change on Boiling..................................................................35

3.3 Experimental ......................................................................................................36


3.4.1 Effect of the Heat Capacity Change on Boiling.............................................37

3.4.2 Effect of the Heat Capacity Change on Melting ............................................38

3.4.3 Final Vapor Pressure Equation.......................................................................39

3.4.4 Temperature Dependence of Vapor Pressure .................................................41

3.5 Conclusion .........................................................................................................43

CHAPTER 4: OCTANOL-AIR PARTITION COEFFICIENT .........................................44

8


4.1 Introduction........................................................................................................44

4.2 Background........................................................................................................44

4.2.1 Octanol Solubility ..........................................................................................45

4.2.2 Saturated Vapor Pressure ...............................................................................46

4.2.3 Octanol-air Partition Coefficient....................................................................46

4.3 Experimental ......................................................................................................47


4.4.1 Final Octanol-air Partition Coefficient Equation ...........................................47

4.4 Conclusion .........................................................................................................51

CHAPTER 5: AIR-WATER PARTITION COEFFICIENT...............................................52

5.1 Introduction........................................................................................................52

5.2 Background........................................................................................................52

5.2.1 Saturated Vapor Pressure ...............................................................................53

5.2.2 Aqueous Solubility.........................................................................................54

5.2.3 Final Air-water Partition Coefficient Equation ..............................................54

5.3 Experimental ......................................................................................................55


5.4.1 Non-ionizable Compounds and Those with Solubilities Less than 50%.......57

5.4.2 Ionizable Compounds and Those with Solubilities Greater than 50% ..........58

9


5.5 Conclusion .........................................................................................................60

APPENDIX A: ESTIMATION OF OCTANOL SOLUBILITY........................................61

APPENDIX B: RESULTS OF VAPOR PRESSURE ESTIMATIONS.............................64

APPENDIX C: RESULTS OF THE OCTANOL-AIR PARTITION COEFFICIENT

ESTIMATIONS .................................................................................................................87

APPENDIX D: RESULTS OF THE AIR-WATER PARTITION COEFFICIENT

ESTIMATIONS FOR NON-IONIZABLE COMPOUNDS AND THOSE WITH

AQUEOUS SOLUBILITIES OF LESS THAN 50%……………………………………94

APPENDIX E: RESULTS OF THE AIR-WATER PARTITION COEFFICIENT

ESTIMATIONS FOR IONIZABLE COMPOUNDS AND THOSE WITH AQUEOUS

SOLUBILITIES OF GREATER THAN 50% .................................................................108

REFERENCES ................................................................................................................112

10

LIST OF FIGURES

Figure 1.1 Flow diagram illustrating measures of partitioning and volatility. ................. 14

Figure 2.1 Dependence of octanol solubility on melting points. ...................................... 29

Figure 3.1 Log of the experimental and predicted vapor pressures in atmospheres......... 40

Figure 3.2 Vapor pressure of anthracene as a function of temperature. ........................... 42

Figure 4.1 Log of the experimental and predicted octanol-air partition coefficients. ...... 48

Figure 4.2 Error distribution as a function of reported octanol-air partition coefficients. 49

Figure 5.1 Experimental and predicted air-water partition coefficients for non-ionizable

compounds and those with aqueous solubilities less than 50%........................................ 57

Figure 5.2 Experimental and predicted air-water partition coefficients for ionizable

compounds and those with aqueous solubilities greater than 50%................................... 59

11

LIST OF TABLES

Table 2.1 Liquid molar volumes and corresponding ranges of complete miscibility with

octanol............................................................................................................................... 21

Table 2.2 Miscibility data of 32 common organic liquid solutes in octanol..................... 27

Table 3.1 Log of the average absolute errors and average errors for the estimation of the

ambient temperature vapor pressure of 680 liquid organic compounds. .......................... 37


ambient temperature vapor pressures of 135 solid organic compounds. .......................... 38


ambient temperature vapor pressures of 815 organic compounds.................................... 39

Table 4.1 Octanol-air Partition Coefficient of Chlorobenzenes at 298K………………...50

12

ABSTRACT

The United States Environmental Protection Agency was established in 1970 to control,

limit, and regulate pollutant entry into the environment. The primary sources of

pollutants are motor vehicle emissions, chemical plants, production factories, land fills,

and natural or man-made catastrophes. Persistent organic pollutants have been known to

cause such aliments as cancer, respiratory disease, and birth defects. These compounds

can also cause irreversible environmental effects such as ozone depletion.

The amounts of pollutants in air, water, soil, and organic matter can be correlated with

the octanol solubility, vapor pressure, octanol-air partition coefficient, and air-water

partition coefficient. The estimation of physical properties plays an important role in

understanding the fate of organic pollutants. Although it is more desirable to measure

such properties, their estimations can be of great importance in conserving resources and

minimizing exposure.

In this dissertation new equations for the estimation of these properties are generated.

This is accomplished without the use of fitted parameters or regression analysis. The

only experimental input parameters are the transition temperatures. The transition

properties were estimated from molecular structure. The average absolute errors for the

estimated properties are less than one log unit from the experimental values.

13

CHAPTER 1: INTRODUCTION

1.1 Overview

Physical properties such as the molar octanol solubility, saturated vapor pressure,

octanol-air partition coefficient, and the air-water partition coefficient are important

descriptors used in assessing the fate of pollutants and establishing environmental

exposure guidelines. Various estimation methods exist for these properties, with some

being restricted to specific chemical classes. These methods provide reliable estimates

for the given structural group of compounds. However, their application to different

classes of compounds may lead to erroneous estimations and their use is further restricted

with the advent of new compounds or functional groups. Thus, it becomes increasingly

desirable to develop a unified estimation approach with wide applicability.

Figure 1.1 is an adaptation of the scheme presented by Yalkowsky et al. (1994) and it

depicts the relationship between the various measures of partitioning and volatility. It

can be seen that knowledge of any two parameters will aid in the estimation of a third

parameter.

14

Soct

Koa Kaw

VP Swat

Figure 1.1 Flow diagram illustrating measures of partitioning and volatility.

For example, developing empirical equations for the molar octanol solubility (Soct) and

saturated vapor pressure (VP) will allow for the estimation of the octanol-air partition

coefficient (Koa) since it represents the equilibrium concentration ratio between air and

octanol. Similarly, the air-water partition coefficient (Kaw), which is the equilibrium

concentration ratio between air and water, can be estimated from empirical equations for

the molar aqueous solubility (Sw) and saturated vapor pressure.

The accuracy of any broadly applicable method relies on the number of assumption made

and the availability of accurately measured data. Boethling et al. (2004) noted that for

broadly applicable estimation methods accuracies of +0.5 to 1 log units, corresponding to

factors of 3-10, are common. This was used as the standard allowable error in estimating

the properties mentioned in the specific aims of this dissertation.

15

1.2 Aims of This Study

The specific aims of this dissertation are to generate empirical equations for:

� The molar octanol solubility (Chapter 2)

� Saturated vapor pressure (Chapter 3)

� Octanol-air partition coefficient (Chapter 4)

� Air-water partition coefficient (Chapter 5)

In Chapter 2 an expression for the molar octanol solubility of organic compounds is

generated from the principles of regular solution theory. Theoretical ranges of complete

miscibility for liquid solutes in octanol are proposed. These ranges are verified using

organic liquids with various degrees of polarity. The molar octanol solubility of a

structurally diverse data set is then estimated from a constant for complete miscibility and

the ideal crystalline term.

The ambient temperature saturated vapor pressures of organic compounds are estimated

in Chapter 3 using the Clausius-Clapeyron equation. The transition properties are

estimated from empirical equations. Previously published equations for the entropies of

melting and boiling are presented. Two new equations are introduced for the estimation

of the heat capacity change on boiling. The estimations regarding the heat capacity

change on melting is revisited. The new vapor pressure equation provides reliable

16

estimations at room temperature. The applicability of the new equation is extended

further by estimating the temperature dependence of vapor pressure for anthracene.

In Chapter 4 the octanol-air partition coefficient is estimated by combing equations for

the molar octanol solubility (Chapter 2) and saturated vapor pressure (Chapter 3). This

new equation is applicable to all organic compounds with solubility parameters in the

range of complete miscibility with octanol.

The air-water partition coefficient is estimated in Chapter 5 by combing equations for the

molar aqueous solubility and saturated vapor pressure (Chapter 3). Since the air-water

partition coefficient estimations are based on dilute solute concentrations in water, the

experimental data set is broken into two categories: ionizable compounds and those with

solubilities of greater than 50%, non-ionizable compounds and those with solubilities of

less than 50%. Finally, the new equation is used to estimate the air-water partition

coefficients of these two data sets.

17

CHAPTER 2: MOLAR OCTANOL SOLUBILITY OF ORGANIC SOLUTES

2.1 Introduction

The purpose of this section is to derive and validate an empirical equation for the

estimation of the molar octanol solubility of organic compounds. The octanol solubility

plays an important role in determining the partitioning and absorption behavior of

environmental and pharmaceutical compounds. Its accurate estimation will allow for

better modeling and understanding the environmental fate of these compounds.

Quantitative structure-property relationships (QSPR) schemes for the prediction of

octanol solubility have been developed, however their applications are limited to specific

classes of compounds (Cousins and Mackay, 2000). Thus, it becomes increasingly

desirable to have an equation that is applicable to all organic compounds.

2.2 Background

2.2.1 Regular Solution Theory

When two liquids are mixed, the resultant solution can be classified as an ideal, solvated,

or regular solution. The principles of regular solution theory are employed here to derive

an empirical equation for the estimation of octanol solubility. According to Hildebrand

and Scott (1950), a regular solution is defined as having an ideal entropy and volume of

18

mixing. Depending on the molecular interactions, the enthalpy of mixing can be positive

(endothermic) or negative (exothermic). The total enthalpy of mixing for a binary system

is given by

xyyyxxmix HHHH ∆−∆+∆=∆ (2.1)

where a positive enthalpy of mixing occurs when the individual component interactions

(xx or yy) are greater than the interaction between the components (xy). This leads to

positive deviations from ideality since the enthalpy of mixing is zero for an ideal

solution. Positive deviation occurs when one component interacts strongly with itself

than with the other components. If the interaction between the two is stronger and more

favored than the individual interactions, the enthalpy of mixing will be negative, leading

to negative deviations from ideality.

2.2.2 Scatchard-Hildebrand Activity Coefficient

While the assumptions regarding regular solution theory are generally useful, they are not

applicable to strongly hydrogen bonded compounds like water. The Scatchard-

Hildebrand equation, which is based on the principals of regular solution theory and

positive deviations from ideality, can be used to estimate an octanol activity coefficient of

solutes. As a first approximation, the use of this equation for a weakly hydrogen bonding

liquid such as octanol is valid. The Scatchard-Hildebrand activity coefficient (γoct) of a

solute in octanol is given by

19

( )TR2.3

δδVγlog

22oct

2oct2

oct ⋅⋅−φ

= (2.2)

where V2 and δ2 are the molar volume and solubility parameter of the solute, respectively.

δoct and octφ denote the solubility parameter and volume fraction of octanol, respectively.

2.2.3 Miscibility of Liquid Solutes with Octanol

The mole fraction (Xoct) solubility of a crystalline compound in octanol is given by

octcidealoct γlogXlogXlog −= (2.3)

where cidealX and γoct are the ideal crystalline solubility and octanol activity coefficient of

a solute, respectively. In the case of liquid compounds at ambient temperature (i.e.

melting point less than 25 °C), the above equation is simplified to

octoct γlogXlog −= (2.4)

where the extent of solubilization of a liquid solute in octanol is limited by its activity

coefficient. Combining Equations 2.2 and 2.4 leads to

( )TR2.3

δδVXlog

22oct

2oct2L

oct ⋅⋅−φ

−= (2.5)

where the extent of solubilization is limited by the molar volume, octanol volume

fraction, and solubility parameter difference. Complete miscibility will generally occur

for solutes with solubility parameters near that of octanol (i.e., δoct = δ2). Thus it becomes

important to derive a range of complete miscibility for liquid solutes in octanol. In order

to estimate their solubility in octanol the following generalization is made. Complete

20

miscibility of liquid solutes in octanol occurs when Xoct=X2= 0.5. This assumption was

used by Hildebrand and Scott (1950) in the determination of the upper critical solution

temperature for the mixture of two liquids. For a solute with a molar volume near that of

octanol, a mole fraction solute solubility of 0.5 corresponds to an octanol volume fraction

( octφ ) of 0.5. For complete miscibility at 298 K Equation 2.5 becomes

( ) ( ) ( )5709

δ1.120.5V0.5log

22

22 −⋅

−= (2.6)

where 21.1 (J/cm3)0.5 is the solubility parameter of octanol, simplifying to

22 δ21.1V9.82 −⋅≥ (2.7)

Thus, from the molar volume of a liquid solute its theoretical range of complete

miscibility in octanol can be obtained from the above equation. For liquid solutes having

solubility parameters outside the calculated range, phase separation occurs upon mixing

with octanol. For a binary system, Hildebrand and Scott (1950) rationalized that it is

more appropriate to use the average molar volume of the two components. Table 2.1 lists

several hypothetical liquid molar volumes along with the calculated ranges of complete

miscibility with octanol. The ranges are calculated from averaging the molar volumes of

the solute and octanol.

21

Table 2.1 Liquid molar volumes and corresponding ranges of complete miscibility with

octanol.

Liquid MolarVolume (cm3/Mol)

Range of CompleteMiscibility (J/cm3)0.5

50 13.0 - 29.2100 13.8 - 28.4158 14.5 - 27.7200 14.9 - 27.3300 15.6 - 26.6400 16.1 - 26.1500 16.5 - 25.7

As the molar volumes increase in Table 2.1, the range of complete miscibility with

octanol decreases. If a liquid solute has a molar volume near that of octanol, i.e., 158

cm3/Mol, Equation 2.7 becomes

2δ21.160.6 −≥ (2.8)

which leads to a solubility parameter range of 15 to 28 (J/cm3)0.5 for liquid solutes that

are completely miscible with octanol. Interestingly, the solubility parameters of most

common environmental and pharmaceutical compounds fall within this range.

Since the molarity of pure dry octanol is 6.33 Mol/L, a mole fraction solubility of 0.5

corresponds to a molar solubility of 3.17 Mol/L. Coincidentally the logarithm of 3.17 is

0.5. If a liquid solute has a solubility parameter in the above range its solubility in

octanol ( LoctS ) can be approximated on a molar scale by

0.5Slog Loct = (2.9)

22

2.2.4 Ideal Crystalline Solubility

For crystalline compounds at ambient temperature, the extent of solubilization is limited

by the ideal crystalline solubility and activity coefficient. The first part of Equation 2.3

accounts for the ideal crystalline solubility, which is the crystal contribution to solubility.

The ideal crystalline solubility is given by

( )

−

−⋅

∆+

⋅⋅⋅−

−=T

Tln

T

TT

R3.2

Cp

TTR2.3

TT∆HXlog mmm

m

mmcideal (2.10)

where ∆Hm, Tm, T are the enthalpy of melting, melting point, and reference temperature,

respectively. ∆Cpm is the heat capacity change on melting. Some workers assume ∆Cpm

is negligible (Liu, 2000), while others assume it is better approximated by the entropy of

melting (Neau and Flynn, 1990). Neither assumption has been shown to be superior. For

simplicity the heat capacity change on melting is assumed negligible and using Gibbs

relationship at the transition temperature leads to

( )TR2.3

TT∆SXlog mmc

ideal ⋅⋅−

−= (2.11)

where the ideal crystalline solubility is determined from the entropy of melting, melting

point, and reference temperature.

2.2.5 Entropy of Melting

Equation 2.11 can be further simplified by the use of Walden’s rule. Walden’s rule states

that the entropy of melting for coal tar derivatives, which are primarily rigid organic

23

compounds, can be approximated by a constant value of 56.5 J/mol·K (Walden, 1908).

Thus

( ) ( )25MP0.015709

298T56.5Xlog mc

ideal −⋅−=−⋅

−= (2.12)

where MP denotes the melting point of a compound in Celsius and 25 °C represents the

experimental temperature of interest. MP-25 is used in place of Tm-298 because melting

point data are normally reported in Celsius.

Recently, Jain et al. (2004) demonstrated that the entropy of melting can be more

accurately approximated by

τ7.4logσ19.150∆Sm ⋅+⋅−= (J/Mol·K) (2.13)

where the σ and τ represent the molecular symmetry and flexibility numbers,

respectively. The molecular symmetry number is defined as the number of ways a

molecule could be superimposed on itself resulting in an identical structure with respect

to a reference position. The molecular flexibility number is given by

1RING0.5SP20.5SP3τ −⋅+⋅+= (2.14)

where SP3, SP2, and RING denote the number of non-ring non-terminal sp3 and sp2

atoms, and RING denotes the number of independent single fused ring systems in a

molecule (Jain et al., 2004). Therefore, the ideal crystalline solubility can be more

accurately estimated by

( ) ( )5709

25MPτ7.4logσ19.1-50Xlog c

ideal

−⋅⋅+⋅−= (2.15)

24

2.2.6 Molar Octanol Solubility

The molar octanol solubility of a crystalline solute ( CoctS ) can be determined from the

product of the solubility it would have if it were a liquid and its ideal crystalline

solubility. This expression is given by

cideal

Loct

Coct XSS ⋅= (2.16)

The two terms on the right hand side of the equation are independent of one another.

Taking the logarithm of both sides and substituting Equations 2.9 and 2.15 into the above

equation leads to

( ) ( )5709

25MPτ7.4logσ19.1500.5Slog C

oct

−⋅⋅+⋅−−= (2.17)

Thus for crystalline solutes with molar volumes near that of octanol and solubility

parameters in the range of 15 to 28 (J/cm3)0.5, the molar octanol solubility can be

estimated by the melting point, symmetry and flexibility numbers. For those crystalline

solutes that obey Walden’s rule for the entropy of melting and have solubility parameters

in the range of complete miscibility with octanol, the equation becomes

( )25MP0.010.5Slog Coct −⋅−= (2.18)

where the molar octanol solubility can be predicted by the melting point alone. It should

be noted that the term in the parentheses cannot be less than zero. Therefore for all

compounds that melt below ambient temperature, the melting point is set to 25 °C and the

(MP – 25) term vanishes.

25

2.3 Experimental

2.3.1 Miscibility Range

The miscibility of 32 common organic liquids at room temperature with octanol was

determined by mixing equal volumes and visual evaluation for phase separation over a

three day period. All liquid solutes were of high purity (>98%) and used as received

without further modification or purification from the following companies: Sigma-

Aldrich, St. Louis, MO; Burdick and Jackson, Morristown, NJ; and AAER Alcohol and

Chemical Co, Shelbyville, Ky.

2.3.2 Molar Solubility

The reported octanol solubility of 123 compounds were taken from the literature

(Yalkowsky et al., 1983; Miller et al., 1985; Kosanovic et al., 1988; Nimi, 1991;

Pinsuwan et al., 1995; Powell et al., 1996; Fletcher et al., 1997; Shiu et al., 1997;

Abraham et al., 2001; Treszczanowicz et al., 2001; Gracin et al., 2002). The melting

points ranged from below room temperature to 485 °C and included environmentally

prevalent compounds such as polycyclic aromatic hydrocarbons, polychlorinated

biphenyls, and polychlorinated benzenes, as well as steroids and nonsteroidal anti-

inflammatory drugs. Multiple solubility values obtained for several compounds from

various sources were used independently without averaging. The molar volumes and

26

solubility parameters of the liquid solutes were determined by the Bondi group

contribution method (Barton, 1979).

2.4 Results and Discussion

2.4.1 Miscibility Range

Table 2.2 summarizes the results of the observed and predicted miscibility data of 32

common organic liquids with octanol. Predicted miscibility data were obtained by use of

Equation 2.7.

27

Table 2.2 Miscibility data of 32 common organic liquid solutes in octanol.

Molar Volume Solubility Parameter MiscibilityLiquid Solute (cm3/mol) (J/cm3)0.5 Obs. Pred.Butane 101 14.7 Y YHexane 130 14.9 Y YAcetonitrile 52 15.2 Y YOctane 162 15.6 Y YEther 105 15.7 Y YHexadecane 131 15.7 Y YCyclohexane 108 16.8 Y Yp-Xylene 123 17.3 Y YIsopropyl Myristate 319 17.5 Y YCarbon tetrachloride 96 17.8 Y YToluene 106 18.2 Y YEthyl acetate 99 18.2 Y YBenzene 89 18.6 Y YChloroform 81 18.7 Y YAcetone 73 20.1 Y YMethylene chloride 65 20.2 Y YAcetic acid 58 21.4 Y YNitrobenzene 102 22.3 Y YPEG 600 350 22.5 Y YButanol 91 23.1 Y YPEG 400 525 23.1 Y YBenzyl alcohol 104 23.8 Y YPropanol 75 24.6 Y YPEG 200 175 26.1 Y YDMSO 73 26.6 Y YEthanol 58 26.6 Y YMethanol 40 29.7 Y YPropylene glycol 74 30.7 Y YEthylene glycol 56 32.7 Y YGlycerin 73 36.1 N NFormamide 40 36.7 N NWater 18 48.0 N N

*Obs, indicates observed miscibility; Pred, predicted miscibility; PEG, polyethyleneglycol; and DMSO, dimethyl sulfoxide.

From the table it can be seen that complete miscibility with octanol occurs for solutes

with solubility parameters ranging from 14 to 32 (J/cm3)0.5. This includes the range of 15

28

to 28 (J/cm3)0.5, which is based on the assumption that a liquid solute has a molar volume

near that of octanol.

Glycerin, formamide, and water have solubility parameters outside their calculated ranges

of complete miscibility and are thus predicted not to be completely miscible with octanol.

This was validated by the presence of two phases when equal volumes of these solutes

were mixed with octanol.

2.4.2 Molar Solubility

Figure 2.1 represents the relationship between the experimental molar solubilities in

octanol and melting point (MP – 25°C). The figure shows that melting point is the

primary determinant of octanol solubility. As the melting point increases, a

corresponding decrease in octanol solubility occurs. The line in the figure is the

theoretical relationship described by Equation 2.18.

29

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

1.0

0 100 200 300 400 500

MP(oC) - 25

log

Soct

Figure 2.1 Dependence of octanol solubility on melting points.

Linear regression analysis was performed with SPSS version 10.0. Regression analysis

was based on 149 solubilities, corresponding to 123 reported solubilities and 26 miscible

liquid solutes from Table 2.3 that lie in the theoretical range of complete miscibility. The

experimental and predicted octanol solubilities are presented in Appendix A.

Mirex, the square point in Figure 2.1 was deemed a statistical outliner and not included in

the regression analysis, which resulted in ( )25MP0.00990.378logSCoct −⋅−= . This is in

agreement with Equation 2.18. The average absolute error for the predictions for the

entire data set was determined to be 0.39 logarithmic units.

The accuracy in predicting octanol solubility will be limited to the availability of reliable

experimental data and the compounds having solubility parameters in the range of

30

complete miscibility. The equation also does not account for the self-association of

solutes in octanol.

2.5 Conclusion

A theoretical range of complete miscibility of liquid solutes with octanol was derived

from the Scatchard-Hildebrand equation and validated with a group of common organic

solvents. Molar octanol solubilities ranging over four orders of magnitude were

predicted with a non-regression based equation utilizing melting point as the only

molecular descriptor. The use of experimental entropies of melting resulted in only a

slight improvement in predicting octanol solubilities for 68 compounds having melting

points above ambient temperature. The equation in its current form is unable to account

for strongly hydrogen bonding compounds.

31

CHAPTER 3: SATURATED VAPOR PRESSURE

3.1 Introduction

The aim of this section is to develop an equation for the estimation of the saturated vapor

pressures of organic compounds. The tendency for an environmental contaminant or

pesticide to partition into the atmosphere is determined largely by its vapor pressure

(Mackay et al., 1982). Thus, knowledge of vapor pressure will allow for a better

understanding of the environmental fate of organic compounds.

Recently, Voutsas et al. (2002) demonstrated the successful estimation of saturated vapor

pressures from knowledge of the normal boiling point. This method is based on the

Clausius-Clapeyron equation and the use of an empirically fitted parameter obtained from

regressing vapor pressure data from the melting point up to the normal boiling point for

each compound. Coutsikos et al. (2003) estimated the saturated vapor pressure of organic

compounds from the hypothetical liquid vapor pressure and the entropy of melting. The

latter was estimated from a group contribution approach. Both of these methods are

based on approximations of the Clausius-Clapeyron equation. However they are only

applicable to specific chemical classes and are not applicable to a wide range of

compounds.

Myrdal and Yalkowsky (1997) used the integrated form of the Clausius-Clapeyron

equation to estimate the saturated vapor pressure of a wide range of organic compounds

with reasonable accuracy. This approach requires the melting point, boiling point, and

32

four transition properties: entropy of melting, entropy of boiling, heat capacity change on

melting, and heat capacity change on boiling. Using four empirical relationships for the

estimation of these transition properties for each compound, they estimated the saturated

vapor pressures of 297 organic compounds with a root mean square error of 0.21 log

units, corresponding to a factor of 1.61 (Myrdal and Yalkowsky, 1997). In this work the

equations for the transition properties are reevaluated and a new equation for the

estimation of the saturated vapor pressures is generated and validated using a larger data

set containing over 800 compounds.

3.2 Background

The integrated form of the Clausius-Clapeyron equation permits the estimation of

saturated vapor pressures (VP) in atmospheres at any temperature (T) in Kelvin units and

is given by

( )

−

−⋅

∆+

⋅⋅−∆

−=T

Tln

T

TT

R3.2

Cp

TR3.2

TTSVPlog mmmmm

( )

−

−⋅

∆+

⋅⋅−∆

−T

Tln

T

TT

R3.2

Cp

TR3.2

TTS bbbbb (3.1)

where the saturated vapor pressure is estimated from the melting point (Tm), boiling point

(Tb), entropy of melting (∆Sm), entropy of boiling (∆Sb), heat capacity change on melting

(∆Cpm), and heat capacity change on boiling (∆Cpb). For liquid compounds at ambient

temperature this equation is simplified to

33

( )

−

−⋅

∆+

⋅⋅−∆

−=T

Tln

T

TT

R3.2

Cp

TR3.2

TTSVPlog bbbbb (3.2)

where the saturated vapor pressure is estimated from the boiling point, entropy of boiling,

and heat capacity change on boiling.

Mackay et al. (1982) simplified Equation 3.1 by assuming the heat capacity change on

melting and boiling are negligible. These assumptions lead to

( ) ( )TR3.2

TTS

TR3.2

TTSVPlog bbmm

⋅⋅−∆

−⋅⋅−∆

−= (3.3)

This equation was further simplified by assuming the entropies of melting and boiling

were constant and given by Walden’s (56.5 J/Mol·K) and Trouton’s rule (88 J/Mol·K)

(Mackay et al., 1982). These assumptions along with the universal gas constant (8.314

J/Mol·K) resulted in

( ) ( )T

TT60.4

T

TT95.2VPlog bm −

−−

−= (3.4)

where the saturated vapor pressure was estimated from the melting point, boiling point,

and reference temperature. Although this equation is a simplification of the Clausius-

Clapeyron equation, it is not very accurate for the estimation of saturated vapor pressures.

The assumptions made by Mackay were reevaluated by Mishra & Yalkowsky (1991) and

Myrdal & Yalkowsky (1997). These authors improved the estimation of saturated vapor

pressures by using empirical structure based equations for the entropies of melting and

boiling as well as the heat capacity change on boiling in Equation 3.1.

34

3.2.1 Entropy of Melting

In the previous chapter the method of Jain et al. (2004) was introduced and used to

estimate the entropy of melting (Equation 2.13) and is used here in the estimation of solid

vapor pressures.

3.2.2 Entropy of Boiling

As a first hand approximation the entropy of boiling can be approximated by Trouton’s

rule. This rule states that the entropy of boiling for non-hydrogen bonded organic

compounds is a constant value of 88 J/Mol·K. Myrdal et al. (1996) proposed the

following modification of Trouton’s rule for complex and hydrogen bonded compounds

HBN14214.086Sb ⋅+τ⋅+=∆ (J/Mol·K) (3.5)

where the entropy of boiling is estimated from the molecular flexibility (τ) and hydrogen

bond density number (HBN). The hydrogen bond density number is determined from

MW

2NH33.0COOHOHHBN

⋅++= (3.6)

where OH, COOH, NH2 are the number of hydroxyl, carboxylic acid, and amine groups

on a compound and MW is the molecular weight of the compound. The square root

accounts for competition among multiple hydrogen bonding groups on the same

molecule.

35

3.2.3 Heat Capacity Change on Melting

For simplicity, Hildebrand (1935), Mackay et al. (1982), Mishra & Yalkowsky (1991),

and Myrdal & Yalkowsky (1997) assumed the heat capacity change on melting to be

negligible and approximated by

0Cpm =∆ (J/Mol·K) (3.7)

Several other works, Neau et al. (1989) and Neau & Flynn (1990), suggested that it was

more appropriate to assume the heat capacity change on melting is better approximated

by the entropy of melting, i.e.

mm SCp ∆=∆ (J/Mol·K) (3.8)

3.2.4 Heat Capacity Change on Boiling

Experimental data for the heat capacity change on boiling are scarce due to the difficulty

in obtaining gas phase heat capacities over large temperature ranges. Sanghvi and

Yalkowsky (2006) generated an empirical equation for the estimation of the heat capacity

change on boiling from the enthalpy of vaporization at 298 K and at the boiling point,

and Kirchoff’s equation. Their equation states

HBP40456Cpb ⋅−τ⋅−−=∆ (J/Mol·K) (3.9)

where HBP is the hydrogen bonding parameter and is determined from

NH0628.0HCOOHHBP 2 ⋅++= (3.10)

36

where OH, CO2H, and NH are the number of hydroxyl, carboxyl, and amine groups on a

compound (Sanghvi and Yalkowsky, 2006).

Recently, Sepassi et al. (2006) generated two new empirical equations for the estimation

of the heat capacity change on boiling using the experimental data comprising 291 liquid

organic compounds. The first equation was based on a proposed ratio of the heat

capacity change on boiling to the entropy of vaporization. For the estimation of vapor

pressure, Mackay et al. (1982) found -0.76 [i.e. ∆Cpb = -0.76·∆Sb] to be the best value for

small non-hydrogen bonding compounds with boiling points above 100 °C. From the

experimental entropies of boiling the authors generated the following

τ⋅−−=∆ 31.068Cpb (J/Mol·K) (3.11)

The second equation was obtained from back calculating the heat capacity change on

boiling from Equation 3.2 using the experimental boiling points, entropies of boiling, and

room temperature vapor pressures of the 291 liquid organic compounds. This resulted in

τ1.291∆Cpb ⋅−−= (J/Mol·K) (3.12)

3.3 Experimental

The experimental melting points, boiling points, and vapor pressures were obtained from

MPBWIN version 1.41 provided by the United Stated Environmental Protection Agency.

A total of 815 organic compounds (680 liquid and 135 solid) with reported vapor

pressures ranging from 10-15 to 2.16 atmospheres at 298 K were retained. The boiling

37

points of these compounds ranged from 299 to 809 Kelvin and the melting points ranged

from below ambient temperature to 603 K.


3.4.1 Effect of the Heat Capacity Change on Boiling

Table 3.1 summarizes the estimation of saturated vapor pressures of 680 liquid organic

compounds at ambient temperature from Equation 3.2 by using the empirical equation for

the entropy of boiling and the three different equations for the heat capacity change on

boiling.


ambient temperature vapor pressure of 680 liquid organic compounds.

Heat Capacity Equation AAE AEEquation 3.9 0.16 -0.11Equation 3.11 0.18 -0.15Equation 3.12 0.13 -0.03

The error in the estimation of the liquid vapor pressures is the lowest with the use of

Equation 3.12. Although all three equations estimate the heat capacity change on boiling

from molecular flexibility, the constant in Equation 3.12 is significantly higher than those

in Equation 3.9 and 3.11.

38

3.4.2 Effect of the Heat Capacity Change on Melting

Table 3.2 summarizes the average absolute error and average errors in estimating the

ambient temperature vapor pressures of 135 solid organic compounds. The melting

points of these compounds ranged from 299 to 603 Kelvin. The vapor pressures were

estimated from Equation 3.1 using the empirical equations for the entropies of boiling

and melting along with the three different equations for the heat capacity change on

boiling.


ambient temperature vapor pressures of 135 solid organic compounds.

Estimation ∆Cpm ∆Cpb AAE AEEst 1 Eq 3.7 Eq 3.9 0.56 -0.24Est 2 Eq 3.7 Eq 3.11 0.53 -0.29Est 3 Eq 3.7 Eq 3.12 0.43 0.02Est 4 Eq 3.8 Eq 3.9 0.60 -0.32Est 5 Eq 3.8 Eq 3.11 0.57 -0.37Est 6 Eq 3.8 Eq 3.12 0.44 -0.06

In estimations 1 through 3 and 4 through 6, the heat capacity change on melting was

assumed negligible or equal to the entropy of melting, respectively. These estimations

illustrated that both assumptions result in nearly identical errors. This is because of the

small contribution of

−

−T

Tln

T

TT mm in Equation 3.1 to the overall estimation of vapor

pressure. The two terms in the bracket are similar in magnitude but have opposite signs.

39

The heat capacity change on melting assumption becomes significant for solid

compounds with high melting points.

For the estimations in Table 3.2, the use of Equation 3.12 for the estimation of heat

capacity change on boiling provides the most accuracy in the estimation of the room

temperature solid vapor pressures. The results in this table further show that Equations

3.9 and 3.11 do not estimate solid vapor pressures very well.

3.4.3 Final Vapor Pressure Equation

Table 3.3 presents the errors in the estimation of the ambient temperature vapor pressures

for all compounds in the data set.


ambient temperature vapor pressures of 815 organic compounds.

Estimation ∆Cpm ∆Cpb AAE AEEst 1 Eq 3.7 Eq 3.9 0.23 -0.13Est 2 Eq 3.7 Eq 3.11 0.24 -0.17Est 3 Eq 3.7 Eq 3.12 0.18 -0.03Est 4 Eq 3.8 Eq 3.9 0.23 -0.14Est 5 Eq 3.8 Eq 3.11 0.24 -0.19Est 6 Eq 3.8 Eq 3.12 0.18 -0.04

From the table it can be seen that the use of Equation 3.12 again provides the best overall

estimation of ambient temperature vapor pressures. Thus the final vapor pressure

equation can be illustrated by incorporating Equations 2.13, 3.5, 3.7, 3.12 into Equation

3.1, leading to

40

( )( )TR2.3

TTτ7.4logσ19.150VPlog m

⋅⋅−⋅+⋅−

−=

( )( )TR3.2

TTHBN14214.088 b

⋅⋅−⋅+τ⋅+

−

( )

−

−⋅

⋅−−+

T

Tln

T

TT

R2.3

τ1.291 bb (3.13)

Figure 3.1 depicts the logarithm of the experimental and predicted vapor pressures of all

compounds in the data set. The line in the figure is the line of identity.

-15.0

-10.0

-5.0

0.0

-15.0 -10.0 -5.0 0.0

Predicted log Vapor Pressure

Exp

erim

enta

llog

Vap

orP

ress

ure.

Figure 3.1 Log of the experimental and predicted vapor pressures in atmospheres.

The data in the figure demonstrate estimation of saturated vapor pressures at room

temperature over fifteen orders of magnitude with reasonable accuracy with the use of

41

Equation 3.13. The average absolute error is 0.18 log units, corresponding to a factor of

1.5. These errors are well within the normal range of errors for vapor pressure

measurements. According to Coutsikos et al. (2003) experimental vapor pressures for a

compound can vary by as much as 30 to 100%. Spencer and Cliath (1983) noted that

experimental vapor pressures obtained from various references and experimentalists can

vary by a factor of 2-3.

3.4.4 Temperature Dependence of Vapor Pressure

The applicability of Equation 3.13 was extended further by estimating the saturated vapor

pressure of anthracene as a function of temperature. These estimations are shown in

Figure 3.2.

42

-3.50

-3.00

-2.50

-2.00

-1.50

-1.00

-0.50

0.00

400 450 500 550 600 650

Temperature (K)

Log

VP

TbTm

Figure 3.2 Vapor pressure of anthracene as a function of temperature.

The open squares denote the reported vapor pressures as a function of temperature. The

solid line in the figure represents the estimated values obtained from Equation 3.13 and

the vertical dashed lines denote the experimental melting and boiling point of anthracene,

respectively. It can be seen that the new equation is able to predict saturated vapor

pressures up to the normal boiling point.

43

3.5 Conclusion

A new equation based on the integrated form of the Clausius-Clapeyron equation was

used to estimate the room temperature saturated vapor pressures of 815 organic

compounds. It was found to reliably estimate vapor pressures over fifteen orders of

magnitude with an average absolute error of 0.18 logarithmic units, corresponding to a

factor of 1.50. The applicability of the new equation was extended further by estimating

the saturated vapor pressure of anthracene as a model compound as a function of

temperature from values below its melting point up to its boiling point.

44

CHAPTER 4: OCTANOL-AIR PARTITION COEFFICIENT

4.1 Introduction

Inhalation is the most important route of unintentional entry of chemicals into the human

body (Hau et al., 1999). According to the United States Environmental Protection Agency

(www.epa.gov), hazardous air pollutants may cause cancer or other serious health effects,

as well as adverse environmental and ecological effects. The octanol-air partition

coefficient is useful in establishing health guidelines for volatile organic compounds

(Hau et al., 2000).

QSPR schemes have been developed for the estimation of this property but are limited to

specific chemical classes (Chen et al., 2001; Chen et al., 2002a; Chen et al., 2002b; Chen

et al., 2002c; Chen et al., 2003a; Chen et al., 2003b; Puzyn and Falandysz, 2005). The

method of Abrahm et al. (2001) and Meylan & Howard (2005) are notable exceptions to

the QSPR approaches. The aim of this chapter is to generate an equation for the

estimation of the octanol-air partition coefficient. This will be accomplished by

combining empirical relationships for the molar octanol solubility and saturated vapor

pressures of organic compounds.

4.2 Background

45

The octanol-air partition coefficient is commonly used to describe the partitioning of a

solute between the atmosphere and the organic matter in the environment. This

relationship is given by

air

octoa C

CK = (4.1)

where Coct and Cair are the molar concentrations of the solute in octanol and air,

respectively. At saturation, this value can be approximated by the ratio of the molar

octanol solubility (Soct) to the saturated vapor pressure (VP). The latter is divided by RT,

where R is the ideal gas constant in L·atm/mol·K and T is the experimental temperature

in Kelvin units. Thus at saturation the unitless octanol-air partition coefficient can be

estimated from the molar octanol solubility and saturated vapor pressure by

VP/RT

SK oct

oa = (4.2)

This equation illustrates that the octanol-air partition coefficient is simply estimated from

the molar octanol solubility and saturated vapor pressure.

4.2.1 Octanol Solubility

In Chapter 2 the molar octanol solubility of organic compounds was shown to be given

by

( )TR2.3

TT∆S0.5Slog mm

oct ⋅⋅−

−= (4.3)

46

this equation is applicable to solutes with molar volumes near that of octanol and

solubility parameters ranging from 15 to 28 (J/cm3)0.5.

4.2.2 Saturated Vapor Pressure

The saturated vapor pressure of an organic compound was estimated in Chapter 3 using

the integrated form of the Clausius-Clapeyron equation. Vapor pressure estimations

confirmed that it is valid to assume that the heat capacity change on melting is negligible,

leading to

( ) ( )

−−

⋅∆

+⋅⋅−∆

−⋅⋅−∆

−=T

Tln

T

TT

R3.2

Cp

TR3.2

TTS

TR3.2

TTSVPlog bbbbbmm (4.4)

where the transition properties were estimated from empirical structure based equations.

4.2.3 Octanol-air Partition Coefficient

Equation 4.2 permits the estimation of the octanol-air partition coefficient from the molar

octanol solubility and saturated vapor pressure. At 298 K this equation becomes

VP

S24.47K oct

oa

⋅= (4.5)

Taking the logarithm of both sides of this equation and substituting in Equations 4.3 and

4.4 leads to

( )

−−

⋅∆

−⋅⋅−

+=T

Tln

T

TT

R3.2

Cp

TR2.3

TT∆S1.89Klog bbbbb

oa (4.6)

47

where the unitless octanol-air partition coefficient is simply estimated from the boiling

point, entropy of boiling, and heat capacity change on boiling. It should be noted that the

melting point and entropy of melting terms in Equations 4.3 and 4.4 cancel each other.

4.3 Experimental

The experimental octanol-air partition coefficients of 236 organic compounds at ambient

temperature extending over twelve orders of magnitude were obtained from the literature

(Hiatt, 1997; Hiatt, 1998; Weiss, 2000; Ferreira, 2001; Wania et al., 2002; Otvos et al.,

2004; Staikova et al., 2004; William and Howard, 2005). The boiling points of these

compounds ranged from 305 to 808 K and were obtained from MPBPWIN version 1.41

provided by the United States Environmental Protection Agency.


4.4.1 Final Octanol-air Partition Coefficient Equation

The final octanol-air partition coefficient can be illustrated by substituting in the

equations for the entropy of vaporization (Equation 3.5) and heat capacity change on

boiling (Equation 3.12) into Equation 4.6

( )( )TR2.3

TTHBN1421τ0.4861.89logK b

oa ⋅⋅−⋅+⋅+

+=

48

( )

−

−⋅

τ⋅−−−

T

Tln

T

TT

R3.2

2.191 bb (4.7)

This equation is applicable to organic compounds with solubility parameters in the range

of complete miscibility with octanol, i.e. 15 to 28 (J/cm3)0.5. Fortunately this range

includes the vast majority of pharmaceutical and environmentally important compounds.

Figure 4.1 demonstrates the estimation of the room temperature octanol-air partition

coefficients over twelve orders of magnitude.

0.0

5.0

10.0

15.0

0.0 5.0 10.0 15.0

Predicted log Koa

Exp

erim

enta

llo

gK

oa

Figure 4.1 Log of the experimental and predicted octanol-air partition coefficients.

The solid line in the figure is the line of identity. The average absolute error is 0.34 log

units, corresponding to a factor of 2.2. The complete list of compounds, experimental,

and predicted values are provided in Appendix C. Figure 4.2 depicts the error

49

distribution in estimating the octanol-air partition coefficient as a function of the reported

values.

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

0.0 5.0 10.0 15.0

Experimental log Koa

Exp

-Pre

d

Figure 4.2 Error distribution as a function of reported octanol-air partition coefficients.

Note, from the total number of compounds, only 7 predicted values are more than one log

unit from the experimental values. To illustrate the range of reported octanol-air partition

coefficients, experimental values for the Chlorobenzenes obtained from various

references are presented in Table 4.1.

50

Table 4.1 Octanol-air Partition Coefficient of Chlorobenzenes at 298 K.

Name log Koaa log Koa

b log Koac Avg Std Dev log Koa

d AECBZ 3.31 3.741,2-D2CBZ 4.99 4.48 4.36 4.61 0.33 4.71 0.101,3-D2CBZ 4.89 4.27 4.12 4.43 0.41 4.56 0.131,4-D2CBZ 4.92 4.32 4.46 4.57 0.31 4.56 0.011,2,3-T3CBZ 5.65 5.32 5.19 5.39 0.24 5.51 0.121,2,4-T3CBZ 5.54 5.10 4.95 5.20 0.31 5.41 0.211,3,5-T3CBZ 5.38 4.89 4.85 5.04 0.30 5.29 0.251,2,3,4-T4CBZ 6.25 5.83 5.64 5.91 0.31 6.28 0.371,2,3,5-T4CBZ 6.09 5.78 5.55 5.81 0.27 6.11 0.301,2,4,5-T4CBZ 6.10 5.80 5.63 5.84 0.24 6.07 0.23P5CBZ 6.75 6.50 6.49 6.58 0.15 6.79 0.21H6CBZ 7.55 7.88

aReported values of Lei et al. bReported values of Staikova et al. cReported values ofMeylan & Howard. dEstimated from Equation 4.7.

The average reported values and standard deviations were determined except for

chlorobenzene and hexachlorobenzene in Table 4.1. For these two compounds multiple

experimental values were not found in the literature. The absolute error was determined

by taking the absolute difference between the average reported values and those

estimated by Equation 4.7. For the majority of the compounds the absolute error is in

agreement with the standard deviation of the experimental values. For example, the

experimental log octanol-air partition coefficient of 1,3-dichlorobenzene ranges from

4.12 to 4.89, this range corresponds to a six fold difference between the two values. The

average experimental value for this compound is 4.43 ± 0.41. The predicted value

deviates from the average experimental value by only 0.13 log units, which is less than

the standard deviation of the measurement.

51

4.4 Conclusion

A new non-regression based equation for the estimation of the octanol-air partition

coefficient was developed and validated using a structurally diverse set of compounds.

This equation provides reasonable estimates of the octanol-air partition coefficients from

the boiling point, entropy of boiling, and heat capacity change on boiling. These

transition properties were estimated from independently derived empirical equations.

From the total number of reported octanol-air partition coefficients 97% are estimated to

within one log unit from the reported value.

52

CHAPTER 5: AIR-WATER PARTITION COEFFICIENT

5.1 Introduction

The air-water partition coefficient (Kaw) or Henry’s law constant is a commonly used

descriptor for the equilibrium partitioning of a solute between air and water. The

distribution and accumulation of environmental pollutants are primarily determined from

the air-water partition coefficient. Without the use of experimental methods the risk

assessment of pollutants requires modeling. Current methods for the estimation of this

property include but are not limited to group contributions (Lin & Sandler, 2002),

QSPR’s (Nirmalakhandan et al., 1997; Yao et al., 2002; Dearden & Schuumann, 2003;

Modarresi et al., 2005), LSER (Endo & Schmidt, 2006), neural networking (Taskinen &

Yliruusi, 2003), and bond contribution (Meylan & Howard, 1991). In this chapter an

expression for the air-water partition coefficient is generated from combining empirical

equations for the saturated vapor pressure and molar aqueous solubility.

5.2 Background

The air-water partition coefficient is the solute concentration ratio in air (Cair) and water

(Cw) and is given by

w

airaw C

CK = (5.1)

53

At saturation these concentrations can be approximated by the saturated vapor pressure

(VP) in atmospheres and molar aqueous solubility (Sw)

waw S

VP/RTK = (5.2)

where VP, R, and T are the ideal gas constant and reference temperature. At ambient

conditions (R = 0.0820578 L·atm/mol·K, T = 298 K) this equation becomes

waw S24.47

VPK

⋅= (5.3)

Note that the numerator has the same units as the denominator in the above equation.

5.2.1 Saturated Vapor Pressure

In Chapter 3 the saturated vapor pressure of organic compounds was estimated by

assuming the heat capacity change on melting is negligible. This lead to the following

simplified form of the Clausius-Clapeyron equation

( ) ( )

−

−⋅

∆+

⋅⋅−∆

−⋅⋅−∆

−=T

Tln

T

TT

R3.2

Cp

TR3.2

TTS

TR3.2

TTSVPlog bbbbbmm (5.4)

The first part of this equation accounts for the ideal crystalline solubility whereas the

remaining terms represent the ideal gas solubility. In other words the saturated vapor

pressure in fractional atmosphere units can be expressed as the product of the ideal mole

fraction crystalline and gas solubilities

gideal

cideal XXVP ⋅= (5.5)

54

5.2.2 Aqueous Solubility

The molar aqueous solubility (Sw) of a crystalline compounds in water is given by

ww

cideal

w vγX

S⋅

= (5.6)

where γw and vw are the aqueous activity coefficient and molar volume of water,

respectively. This equation is intended for dilute solute concentrations in water. For

these solutions vw is the molar volume of water (0.0182 L/mol). For compounds that are

extensively solubilized in water the molar volume of water can not be used since the

solute will be present in high concentrations.

5.2.3 Final Air-water Partition Coefficient Equation

Equation 5.3 demonstrates that the air-water partition coefficient can be estimated from

saturated vapor pressures and molar aqueous solubilities. Substituting in Equations 5.5

and 5.6 into this expression leads to

24.47

vγXK ww

gideal

aw

⋅⋅= (5.7)

the above equation illustrates that the air-water partition coefficient is proportional to the

ideal gas solubility, aqueous activity coefficient, and molar volume of water. Note that

the substitutions result in the elimination of the crystal terms. The air-water partition

coefficient can be estimated by Equation 5.7, substituting the ideal gas solubility, and

assuming dilute solute solutions in water

55

( )

−

−⋅

+⋅⋅−

−+−=T

Tln

T

TT

T2.3

∆Cp

TR2.3

TT∆Slogγ3.13Klog bbbbb

waw (5.8)

where the unitless air-water partition coefficient is estimated from the boiling point,

entropy of boiling, heat capacity change on boiling, and aqueous activity coefficient. The

final air-water partition coefficient is obtained by incorporating the equations for the

entropy of vaporization (Equation 3.5) and the heat capacity change on boiling (Equation

3.12) into Equation 5.8

( )( )+

⋅⋅−⋅+⋅+

−+−=TR2.3

TTHBN1421τ0.488γlog3.13Klog b

waw

( )

−

−⋅

⋅−−T

Tln

T

TT

R2.3

τ1.291 bb (5.9)

5.3 Experimental

The experimental boiling points and Henry’s law constants were obtained from

HENRYWIN version 1.90 provided by the United Stated Environmental Protection

Agency. It should be noted that Equation 5.9 requires experimental boiling points as an

input parameter. The equation is applicable to those compounds with known boiling

points that are above 25 °C. This resulted in 658 Henry’s law constants ranging from 4.71

x 10-12 to 12.6 atm·m3/mol. These values were separated into two categories: non-

ionizable compounds and those with aqueous solubilities less than 50% (n = 501),

ionizable compounds and those with aqueous solubilities greater than 50% (n = 157).

56

The aqueous activity coefficients were estimated from the group contribution method of

Jain et al. (2007). These authors used Equation 5.6 and back calculated an effective

aqueous activity coefficient for 1675 organic compounds. These compounds had aqueous

solubilities less than 1.0 mol/l, which was determined to be the maximum solubility a

compound could have and still be considered a dilute solution.

57


5.4.1 Non-ionizable Compounds and Those with Solubilities Less than 50%

Figure 5.1 depicts the logarithm of the experimental and predicted air-water partition

coefficients for the non-ionizable compounds and those with aqueous solubilities of less

than 50%. The solid line in the figure is the line of identity.

-10.0

-8.0

-6.0

-4.0

-2.0

0.0

2.0

-10.0 -8.0 -6.0 -4.0 -2.0 0.0 2.0

Predicted log Kaw

Exp

erim

enta

llog

Kaw

Figure 5.1 Experimental and predicted air-water partition coefficients for non-ionizable

compounds and those with aqueous solubilities less than 50%.

It can be seen that Equation 5.9 provides reasonable estimates over ten orders of

magnitude. The average absolute error is 0.56 log units which corresponds to a factor of

58

3.6. This error is comparable to the normal experimental errors seen in vapor pressure

and solubility measurements. From the total number of compounds in Figure 5.1 87%

are predicted to within one log unit from the experimental value.

The group contribution values for the aqueous activity coefficient are based on aqueous

solubilities of less than 1.0 mol/l (Jain et al., 2007). From the total number of reported

values in Figure 5.2, 16 have experimental aqueous solubilities greater than 1.0 mol/l and

are identified with an asterisk in the supporting information. The air-water partition

coefficients are estimated to within one log unit for the majority of these sixteen

compounds. Since these estimates agree with the experimental values, it indicates that

the measured values were most likely obtained from dilute solutions. The complete list of

compounds, experimental, and predicted values are provided in Appendix D.

5.4.2 Ionizable Compounds and Those with Solubilities Greater than 50%

Figure 5.2 depicts the logarithm of the experimental and predicted air-water partition

coefficients for the ionizable compounds and those with aqueous solubilities of greater

than 50%.

59

-10.0

-8.0

-6.0

-4.0

-2.0

0.0

2.0

-10.0 -8.0 -6.0 -4.0 -2.0 0.0 2.0

Predicted log Kaw

Exp

erim

enta

llog

Kaw

Figure 5.2 Experimental and predicted air-water partition coefficients for ionizable

compounds and those with aqueous solubilities greater than 50%.

From the figure it can be seen that Equation 5.9 provides poor estimations for these

compounds. The average absolute error is 1.10 log units corresponding to a factor of

12.6. The larger error seen here is most likely do to the water being saturated with these

highly soluble solutes and the aqueous activity coefficient estimations not accounting for

ionization.

60

5.5 Conclusion

An equation for the estimation of the air-water partition coefficient was generated from

empirical equation for the molar aqueous solubility and saturated vapor pressure. This

equation was used to estimate the air-water partition coefficients for two data sets. The

first data set represented non-ionizable compounds and those with aqueous solubilities

less than 50%. Air-water partition coefficients were estimated to within one log unit for

87% of these compounds. The second data set represented ionizable compounds and

those with aqueous solubilities greater than 50%. The results of these estimations were

poor, indicating that the use of the molar volume of water was inappropriate and the

aqueous activity coefficient estimations not accounting for ionization.

61

APPENDIX A: ESTIMATION OF OCTANOL SOLUBILITY

Table A.1 Predicted molar solubilities obtained from Equation 2.17.

Exper Pred AbsoluteCompound MP (°C) log Soct log Soct Error1,2,3,5-Tetrachlorobenzene 55 0.15 0.27 0.121,2,3-Trichlorobenzene 53 0.18 0.29 0.111,2,3-Trichlorobenzene 53 0.09 0.29 0.201,2,4,5-Tetrabromobenzene 182 -1.32 -0.56 0.761,2,4,5-Tetrachlorobenzene 139 -0.92 -0.27 0.651,2,4,5-Tetrachlorobenzene 139 -1.08 -0.27 0.811,2,4-Tribromobenzene 43 -0.15 0.34 0.491,3,5-Tribromobenzene 124 -0.90 -0.11 0.791,3,5-Trichlorobenzene 65 -0.16 0.25 0.411,4-Dibromobenzene 87 -0.30 0.08 0.381,4-Dichlorobenzene 53 0.25 0.31 0.061,4-Dichlorobenzene 53 0.20 0.31 0.111,4-Dichlorobenzene 53 0.11 0.31 0.201-Methylfluorene 85 -0.56 -0.03 0.532,3,4-Trichloronitrobenzene 56 -0.29 0.23 0.522,3,5,6-Tetrachloronitrobenezne 100 -0.68 -0.08 0.602,3-Benzanthracene 341 -2.28 -1.63 0.642,3-Benzofluorene 208 -1.75 -1.10 0.652,4,6-Trichlorophenol 70 0.22 0.16 0.062,4-Dichlorophenol 45 0.36 0.32 0.042-Methyl-4-nitroimidazole 252 -1.77 -1.49 0.283,4-Dichloronitrobenzene 41 -0.08 0.36 0.44Acenaphthene 94 -0.59 -0.03 0.56Acetanilide 114 -0.12 -0.40 0.28Acetylsalicyclic acid 135 -0.69 -0.68 0.01Anthracene 216 -1.78 -0.79 0.99Anthracene 216 -1.91 -0.79 1.12Antipyrene 111 -0.19 -0.25 0.06Atrazine 175 -1.32 -1.49 0.17Barbital 190 -0.92 -1.27 0.35Benzil 95 -0.89 -0.20 0.69Benzo[a]Pyrene 179 -1.60 -0.85 0.75Benzoic acid 122 -0.06 -0.25 0.19Benzoic acid 122 -0.95 -0.25 0.70beta-Carotene 180 -0.75 -0.86 0.11

62

Bibenzyl 52 -0.35 0.19 0.54Biphenyl 69 -0.13 0.20 0.33Butyl p-Aminobenzoate 58 0.13 0.04 0.09Butyl p-hydroxybenzoate 69 0.34 -0.11 0.45Caffeine 238 -1.72 -1.37 0.35Chrysene 258 -2.51 -1.31 1.20Chrysene 258 -2.60 -1.31 1.29Coronene 438 -2.37 -1.63 0.74Cortisone 222 -1.97 -1.48 0.49Decachlorobiphenyl 306 -2.77 -1.40 1.37Deoxycorticosterone 142 -0.71 -0.68 0.03Dibenz[a,h]anthracene 270 -3.03 -1.40 1.63Dibenzofuran 82 -0.27 0.06 0.33Dieldrin 175 -0.97 -0.81 0.16Dimetridazole 140 -1.11 -0.51 0.60Diphenylamine 52 0.03 0.23 0.20Diphenylethane 25 -0.66 0.50 1.16Diuron 159 -1.14 -1.02 0.12Endrin 200 -0.94 -1.03 0.09Ethyl p-Aminobenzoate 89 -0.31 -0.23 0.08Ethyl p-hydroxybenzoate 116 0.04 -0.53 0.57Fenchlorphos 35 -0.16 0.37 0.53Fenuron 134 -0.77 -0.73 0.04Fenuron 134 -0.77 -0.73 0.04Fluoranthene 108 -0.76 -0.23 0.53Fluorene 112 -0.62 -0.17 0.45Fluorodifen 94 -1.52 -0.28 1.24Flurbiprofen 111 -0.20 -0.42 0.22Gentisic acid 205 -0.13 -1.08 0.95Heptachlor 95 -0.63 -0.79 0.16Hexachlorobenzene 230 -1.82 -0.56 1.26Hexachlorobenzene 230 -1.86 -0.56 1.30Hexachloroethane 187 -0.28 -0.50 0.22Hexamethylbenzene 164 -0.89 -0.22 0.67Ibuprofen 76 0.18 -0.15 0.33Ipronidazole 61 -0.06 0.17 0.23Isazophos 25 0.50 0.50 0.00Ketoprefen 94 -0.26 -0.28 0.02Ketoprefen 94 -0.10 -0.28 0.18Lindane 113 -0.74 -0.84 0.10m-Bromobenzoic acid 157 -0.07 -0.66 0.59Metalaxyl 72 -0.33 -0.25 0.08Methyl p-aminobenzoate 114 -0.53 -0.39 0.14Methyl p-hydroxybenzoate 131 -0.08 -0.57 0.49

63

Methyltestosterone 163 -0.45 -0.71 0.26Metolachlor 25 0.47 0.50 0.03Metoxuron 127 -1.06 -0.78 0.28Metronidazole 160 -1.53 -1.03 0.49Mirex 485 -0.51 -3.53 3.02Monuron 172 -1.04 -1.17 0.13Naphthalene 80 -0.15 0.13 0.28Naphthalene 80 -0.36 0.13 0.49Naproxen 153 -0.89 -0.95 0.06o,p'-DDT 75 -0.49 -0.06 0.43o-Bromobenzoic acid 146 -0.12 -0.56 0.44p,p-DDT 109 -0.79 -0.45 0.34p,p-DDT 109 -0.98 -0.45 0.53p-Aminobenzoic acid 189 -0.80 -0.77 0.03p-Aminobenzoic acid 189 -1.68 -0.77 0.91p-Bromobenzoic acid 252 -1.11 -1.26 0.15PCB-15 149 -0.89 -0.34 0.55PCB-29 76 -0.75 0.05 0.80PCB-3 78 -0.22 0.09 0.31PCB-52 87 -0.63 0.02 0.65PCB-61 91 -0.85 -0.08 0.78Pentachlorobenzene 86 -0.56 0.03 0.59Pentachlorobenzene 86 -0.63 0.03 0.66Pentachlorophenol 174 -0.11 -0.65 0.54Perlyene 277 -2.52 -1.20 1.32Phenacetin 135 -0.84 -0.89 0.05Phenanthracene 99 -0.45 -0.07 0.38Phenanthracene 99 -0.53 -0.07 0.46Phenobarbital 176 -1.09 -1.02 0.07Phenol 41 0.94 0.38 0.56Prednisolone 240 -1.62 -1.66 0.04Profluralin 32 -0.20 0.40 0.60Progesterone 131 -0.71 -0.43 0.28Propyl p-hydroxybenzoate 96 0.36 -0.40 0.76p-Toluic acid 180 -0.32 -0.70 0.38Pyrene 156 -0.90 -0.38 0.52Pyrene 156 -0.95 -0.38 0.57Salicylic acid 158 0.15 -0.66 0.81Terbutyrne 105 -0.27 -0.67 0.40Testosterone 155 -0.49 -0.64 0.15Theophylline 272 -1.99 -1.66 0.33trans-Stilbene 125 -1.10 -0.40 0.70Triazolam 224 -2.05 -1.24 0.81Triphenylene 199 -1.77 -0.85 0.92

64

APPENDIX B: RESULTS OF VAPOR PRESSURE ESTIMATIONS

Table B.1 Chemical Name, Molecular weight, Melting Point, Boiling Point,

Experimental & Estimated Vapor Pressure and Absolute Errors.

Tm Tb Exp. Est.Chemical Name MW (K) (K) log VP log VP AEHydrocyanic acid 27.0 <298.2 298.8 0.004 -0.01 0.01Methanol 32.0 <298.2 338.0 -0.80 -0.95 0.15Acetonitrile 41.1 <298.2 354.8 -0.92 -0.93 0.01Acetonitrile 41.1 <298.2 355.0 -0.90 -0.93 0.03Aziridine 43.1 <298.2 329.0 -0.60 -0.54 0.06Aziridine 43.1 <298.2 329.2 -0.54 -0.54 0.01Formamide 45.0 <298.2 493.2 -4.08 -3.98 0.10Formic acid 46.0 <298.2 373.0 -1.30 -1.66 0.36Ethanol 46.1 <298.2 351.0 -1.10 -1.15 0.05Hydrazine, methyl- 46.1 <298.2 360.7 -1.17 -1.13 0.03Acrylonitrile 53.1 <298.2 350.0 -0.80 -0.85 0.052-Propenenitrile 53.1 <298.2 350.5 -0.83 -0.85 0.022-Butyne 54.1 <298.2 300.2 -0.02 -0.03 0.01Propanenitrile 55.1 <298.2 370.3 -1.19 -1.21 0.02Propionitrile 55.1 <298.2 370.4 -1.23 -1.21 0.022-Propenal 56.1 <298.2 325.8 -0.43 -0.43 0.01Acrolein 56.1 <298.2 326.0 -0.47 -0.44 0.032-Propyn-1-ol 56.1 <298.2 386.8 -1.67 -1.90 0.23Methane, isocyanato- 57.1 <298.2 312.7 -0.33 -0.22 0.102-Propen-1-amine 57.1 <298.2 326.5 -0.48 -0.48 0.00Aziridine, 2-methyl- 57.1 <298.2 339.2 -0.82 -0.71 0.11Ethanedial 58.0 <298.2 323.6 -0.46 -0.40 0.06Oxirane, methyl- 58.1 <298.2 307.1 -0.14 -0.14 0.00Oxetane 58.1 <298.2 320.8 -0.36 -0.35 0.00Propionaldehyde 58.1 <298.2 321.0 -0.40 -0.36 0.04Propanal 58.1 <298.2 321.2 -0.37 -0.36 0.012-Propanone 58.1 <298.2 328.7 -0.50 -0.48 0.02Acetone 58.1 <298.2 329.0 -0.50 -0.49 0.01Ally alcohol 58.1 <298.2 370.0 -1.40 -1.51 0.112-Propanamine 59.1 <298.2 305.6 -0.10 -0.12 0.02Formamide, N-methyl- 59.1 <298.2 472.7 -3.46 -3.44 0.02

65

Formic acid, methyl ester 60.1 <298.2 305.2 -0.10 -0.11 0.01Hydrazine, 1,1-dimethyl- 60.1 <298.2 337.1 -0.67 -0.67 0.001,2-Dimethyl hydrazine 60.1 <298.2 354.2 -1.02 -1.06 0.042-Propanol 60.1 <298.2 355.5 -1.21 -1.18 0.031,2-Ethanediamine 60.1 <298.2 389.7 -1.79 -1.80 0.01Acetic acid 60.1 <298.2 390.0 -1.80 -1.95 0.15Methane, nitro- 61.0 <298.2 374.3 -1.31 -1.28 0.03Ethanol, 2-amino- 61.1 <298.2 444.2 -3.26 -3.42 0.16Ethanethiol 62.1 <298.2 308.2 -0.14 -0.15 0.01Ethylene glycol 62.1 <298.2 470.0 -3.90 -4.16 0.261,2-Ethanediol 62.1 <298.2 470.5 -3.90 -4.17 0.271,3-Cyclopentadiene 66.1 <298.2 314.2 -0.23 -0.25 0.02Cyclopentadiene 66.1 <298.2 315.0 -0.25 -0.26 0.012-Propenenitrile, 2-methyl- 67.1 <298.2 363.5 -1.01 -1.08 0.07Furan 68.1 <298.2 304.6 -0.09 -0.10 0.012-Methyl-1,3-butadiene 68.1 <298.2 307.0 -0.12 -0.14 0.021,3-Butadiene, 2-methyl- 68.1 <298.2 307.2 -0.13 -0.14 0.011-Pentyne 68.1 <298.2 313.0 -0.25 -0.23 0.023-Methyl-1,2-butadiene 68.1 <298.2 313.0 -0.25 -0.23 0.021,3-Pentadiene, (E)- 68.1 <298.2 315.2 -0.25 -0.26 0.01Cyclopentene 68.1 <298.2 317.0 -0.31 -0.29 0.021,2-Pentadiene 68.1 <298.2 318.0 -0.32 -0.31 0.012,3-Pentadiene 68.1 <298.2 321.0 -0.38 -0.36 0.022-Pentyne 68.1 <298.2 329.0 -0.51 -0.49 0.02Propanenitrile, 2-methyl- 69.1 <298.2 377.1 -1.35 -1.33 0.02Butanenitrile 69.1 <298.2 390.8 -1.58 -1.59 0.02Divinyl ether 70.1 <298.2 301.5 -0.04 -0.05 0.011-Pentene 70.1 <298.2 303.0 -0.08 -0.07 0.012-Methyl-1-butene 70.1 <298.2 304.0 -0.10 -0.09 0.011-Butene, 2-methyl- 70.1 <298.2 304.2 -0.08 -0.09 0.012-Pentene (trans) 70.1 <298.2 309.0 -0.18 -0.17 0.012-Pentene, (Z)- 70.1 <298.2 309.5 -0.17 -0.17 0.002-Pentene, (E)- 70.1 <298.2 309.5 -0.16 -0.17 0.012-pentene (cis) 70.1 <298.2 310.0 -0.19 -0.18 0.012-Methyl-2-butene 70.1 <298.2 312.0 -0.22 -0.21 0.01Cyclopentane 70.1 <298.2 322.0 -0.39 -0.37 0.022-Propenal, 2-methyl- 70.1 <298.2 341.6 -0.69 -0.70 0.02Crotoadehyde 70.1 <298.2 377.0 -1.30 -1.33 0.032-Butenal, (E)- 70.1 <298.2 377.2 -1.29 -1.34 0.05Propanenitrile, 3-hydroxy- 71.1 <298.2 494.2 -3.96 -4.39 0.42

66

2-Propenamide 71.1 357.7 466.2 -5.02 -3.78 1.24Ethene, ethoxy- 72.1 <298.2 309.2 -0.16 -0.17 0.01Isobutylaldehyde 72.1 <298.2 336.0 -0.60 -0.61 0.01Oxirane, ethyl- 72.1 <298.2 336.5 -0.61 -0.61 0.00Propanal, 2-methyl- 72.1 <298.2 337.7 -0.63 -0.63 0.01Furan, tetrahydro- 72.1 <298.2 338.2 -0.66 -0.64 0.012-Butanone 72.1 <298.2 352.7 -0.89 -0.89 0.01Methyl ethyl ketone 72.1 <298.2 353.0 -0.90 -0.90 0.00Acrylic acid 72.1 <298.2 412.0 -2.30 -2.39 0.092-Propenoic acid 72.1 <298.2 414.4 -2.26 -2.44 0.18Butane, 2-methyl- 72.2 <298.2 303.2 -0.03 -0.08 0.05Pentane 72.2 <298.2 309.3 -0.17 -0.17 0.00Pentane 72.2 <298.2 309.3 -0.16 -0.17 0.022-Propanamine, 2-methyl- 73.1 <298.2 317.2 -0.30 -0.31 0.022-Butanamine 73.1 <298.2 336.2 -0.62 -0.65 0.031-Propanamine, 2-methyl- 73.1 <298.2 340.9 -0.72 -0.73 0.02Dimethyl formamide 73.1 <298.2 426.0 -2.30 -2.41 0.11Formamide, N,N-dimethyl- 73.1 <298.2 426.2 -2.28 -2.27 0.01Ethane, 1,1'-oxybis- 74.1 <298.2 307.8 -0.14 -0.15 0.01Formic acid, ethyl ester 74.1 <298.2 327.6 -0.48 -0.47 0.01Acetic acid, methyl ester 74.1 <298.2 330.1 -0.53 -0.51 0.021,3-Dioxolane 74.1 <298.2 351.2 -0.97 -0.87 0.10t-Butanol 74.1 <298.2 356.0 -1.30 -1.15 0.152-Butanol 74.1 <298.2 372.0 -1.60 -1.49 0.11Isobutanol 74.1 <298.2 381.0 -1.80 -1.69 0.11Butanol 74.1 <298.2 391.0 -2.10 -1.91 0.19Propionic acid 74.1 <298.2 414.0 -2.30 -2.43 0.132-Propanol, 2-methyl- 74.1 298.6 355.6 -1.25 -1.14 0.112-Propanol, 1-amino- 75.1 <298.2 433.2 -3.19 -3.01 0.191-Propanol, 3-amino- 75.1 <298.2 460.7 -3.98 -3.71 0.27Methane, dimethoxy- 76.1 <298.2 315.2 -0.27 -0.27 0.00Carbon disulfide 76.1 <298.2 319.2 -0.31 -0.33 0.01Ethaneperoxoic acid 76.1 <298.2 383.2 -1.71 -1.73 0.022-Methoxyethanol 76.1 <298.2 397.0 -1.90 -2.05 0.15Ethanol, 2-methoxy- 76.1 <298.2 397.3 -1.89 -2.05 0.161,2-Propanediol 76.1 <298.2 460.8 -3.76 -3.74 0.011,3-Propanediol 76.1 <298.2 487.6 -4.22 -4.46 0.231-Propanethiol 76.2 <298.2 341.0 -0.68 -0.69 0.013-Chloropropene 76.5 <298.2 318.0 -0.30 -0.31 0.011-Propene, 3-chloro- 76.5 <298.2 318.3 -0.30 -0.31 0.01

67

Benzene 78.1 <298.2 353.3 -0.90 -0.90 0.00Methane, sulfinylbis- 78.1 <298.2 462.2 -3.08 -3.00 0.08Acetyl chloride 78.5 <298.2 323.9 -0.41 -0.40 0.00Pyridine 79.1 <298.2 388.4 -1.55 -1.54 0.011,3,5-Hexatriene 80.1 <298.2 351.0 -0.93 -0.87 0.061,3-Cyclohexadiene 80.1 <298.2 354.0 -0.90 -0.92 0.021,4-Cyclohexadiene 80.1 <298.2 359.0 -1.06 -1.00 0.06Ethanol, 2-chloro- 80.5 <298.2 401.8 -2.01 -2.13 0.111,5-Hexadiene 82.2 <298.2 333.0 -0.54 -0.56 0.021-Hexyne 82.2 <298.2 344.0 -0.75 -0.75 0.002,3-Dimethyl-1,3-butadiene 82.2 <298.2 346.0 -0.71 -0.78 0.071-Methylcyclopentene 82.2 <298.2 349.0 -0.82 -0.83 0.013-Hexyne 82.2 <298.2 355.0 -0.94 -0.94 0.00Cyclohexene 82.2 <298.2 356.2 -0.93 -0.95 0.02Pentanenitrile 83.1 <298.2 414.5 -2.00 -2.06 0.06Thiophene 84.1 <298.2 357.2 -0.97 -0.97 0.01Cyclopentanone 84.1 <298.2 403.7 -1.81 -1.83 0.023,3-Dimethyl-1-butene 84.2 <298.2 314.0 -0.25 -0.25 0.003-Methyl-1-pentene 84.2 <298.2 324.0 -0.46 -0.41 0.054-Methyl-1-pentene 84.2 <298.2 327.0 -0.45 -0.46 0.012,3-Dimethyl-1-butene 84.2 <298.2 328.8 -0.47 -0.49 0.022,3-Dimethyl-1-butene 84.2 <298.2 329.0 -0.79 -0.49 0.30cis-4-Methyl-2-penten 84.2 <298.2 329.0 -0.50 -0.49 0.01trans-4-Methyl-2-pentene 84.2 <298.2 332.0 -0.54 -0.54 0.00trans-4-Methyl-2-pentene 84.2 <298.2 332.2 -0.52 -0.54 0.03Trans-4-Methyl-2-pentene 84.2 <298.2 332.2 -0.48 -0.54 0.062-Methyl-1-pentene 84.2 <298.2 334.0 -0.60 -0.58 0.021-Hexene 84.2 <298.2 336.0 -0.62 -0.61 0.012-Hexene (trans-) 84.2 <298.2 338.2 -0.68 -0.65 0.032-Methyl-2-pentene 84.2 <298.2 340.0 -0.69 -0.68 0.01cis-3-Hexene 84.2 <298.2 340.0 -0.67 -0.68 0.01trans-3-Hexene 84.2 <298.2 340.0 -0.69 -0.68 0.01cis-3-Methyl-2-pentene 84.2 <298.2 341.0 -0.69 -0.69 0.002-hexene (cis) 84.2 <298.2 342.0 -0.71 -0.71 0.00trans-3-Methyl-2-pentene 84.2 <298.2 344.0 -0.74 -0.75 0.01Methylcyclopentane 84.2 <298.2 345.0 -0.72 -0.76 0.042,3-Dimethyl-2-butene 84.2 <298.2 346.0 -0.49 -0.78 0.29Cyclohexane 84.2 <298.2 354.2 -0.90 -0.92 0.02Methane, dichloro- 84.9 <298.2 313.2 -0.23 -0.23 0.00Propanenitrile, 2-hydroxy-2- 85.1 <298.2 444.2 -2.99 -3.06 0.07

68

methyl-2-Pyrrolidinone 85.1 <298.2 518.2 -4.56 -4.39 0.17Acetic acid ethenyl ester 86.1 <298.2 345.7 -0.91 -0.77 0.142-Propenoic acid, methyl ester 86.1 <298.2 353.4 -0.93 -0.91 0.022-Butanone, 3-methyl- 86.1 <298.2 367.5 -1.15 -1.16 0.012-Pentanone 86.1 <298.2 375.4 -1.32 -1.31 0.012-Propenoic acid, 2-methyl- 86.1 <298.2 436.2 -2.88 -2.87 0.012(3H)-Furanone, dihydro- 86.1 <298.2 477.2 -3.21 -3.31 0.10(Z)-2-Butenoic acid 86.1 345.2 458.2 -3.10 -3.79 0.70Piperazine 86.1 379.2 419.2 -3.66 -3.05 0.612,2-Dimethylbutane 86.2 <298.2 323.0 -0.38 -0.39 0.012,3-Dimethylbutane 86.2 <298.2 331.0 -0.52 -0.52 0.002-Methylpentane 86.2 <298.2 333.0 -0.56 -0.56 0.00Hexane 86.2 <298.2 342.2 -0.70 -0.72 0.02Morpholine 87.1 <298.2 402.0 -1.90 -1.89 0.01N,N-dimethyl-acetamide 87.1 <298.2 438.2 -2.57 -2.52 0.05Formic acid, 1-methylethylester 88.1 <298.2 341.4 -0.73 -0.70 0.03Ethyl acetate 88.1 <298.2 350.0 -1.50 -0.85 0.65Acetic acid ethyl ester 88.1 <298.2 350.3 -0.90 -0.86 0.04Propanoic acid, methyl ester 88.1 <298.2 353.0 -0.94 -0.90 0.04Dioxane 88.1 <298.2 374.0 -1.30 -1.27 0.03Propanoic acid, 2-methyl- 88.1 <298.2 427.6 -2.61 -2.67 0.06Butanoic acid 88.1 <298.2 436.9 -2.89 -2.89 0.002-Butene-1,4-diol (cis-) 88.1 <298.2 508.2 -5.05 -4.87 0.18Propane, 2-methoxy-2-methyl- 88.2 <298.2 328.4 -0.47 -0.48 0.012-Butanol, 2-methyl- 88.2 <298.2 375.6 -1.64 -1.53 0.113-Pentanol 88.2 <298.2 389.4 -1.92 -1.83 0.09Thiophene, tetrahydro- 88.2 <298.2 394.2 -1.60 -1.65 0.051-Pentanol 88.2 <298.2 411.0 -2.43 -2.33 0.101,3-Butadiene, 2-chloro- 88.5 <298.2 332.6 -0.53 -0.55 0.012-Nitropropane 89.1 <298.2 393.0 -1.60 -1.63 0.03Propane, 2-nitro- 89.1 <298.2 393.4 -1.63 -1.63 0.00Propane, 1-nitro- 89.1 <298.2 404.3 -1.86 -1.85 0.01Ethanol, 2-(dimethylamino)- 89.1 <298.2 412.2 -3.24 -2.34 0.911,1-Dimethoxyethane 90.1 <298.2 337.0 -0.60 -0.63 0.03Ethane, 1,1-dimethoxy- 90.1 <298.2 337.7 -0.63 -0.64 0.011-Methoxyl-2-propanol 90.1 <298.2 391.0 -1.80 -1.86 0.062-Propanol, 1-methoxy- 90.1 <298.2 392.2 -1.77 -1.89 0.12Ethoxyethanol 90.1 <298.2 408.0 -2.10 -2.25 0.15

69

Ethanol, 2-ethoxy- 90.1 <298.2 408.2 -2.14 -2.26 0.111,4-Butanediol 90.1 <298.2 503.2 -4.85 -4.74 0.102-Propanethiol, 2-methyl- 90.2 <298.2 337.5 -0.61 -0.63 0.02Toluene 92.1 <298.2 384.2 -1.42 -1.46 0.041,3,5-Cycloheptatriene 92.1 <298.2 390.0 -1.61 -1.57 0.041,2,3-Propanetriol 92.1 <298.2 563.2 -6.64 -6.50 0.14Bicyclo[2.2.1]hepta-2,5-diene 92.1 319.0 369.0 -1.06 -1.34 0.28Oxirane, (chloromethyl)- 92.5 <298.2 390.2 -1.65 -1.58 0.07Chloroacetone 92.5 <298.2 393.0 -1.80 -1.63 0.172-Propanone, 1-chloro- 92.5 <298.2 393.2 -1.79 -1.64 0.15Propane, 2-chloro-2-methyl- 92.6 <298.2 323.2 -0.39 -0.39 0.01Butane, 1-chloro- 92.6 <298.2 351.8 -0.86 -0.89 0.02Pyridine, 2-methyl- 93.1 <298.2 402.5 -1.82 -1.81 0.01Pyridine, 3-methyl- 93.1 <298.2 417.3 -2.08 -2.10 0.01Pyridine, 4-methyl- 93.1 <298.2 418.5 -2.11 -2.12 0.01Benzenamine 93.1 <298.2 457.3 -3.18 -3.03 0.15Phenol 94.1 314.0 455.0 -3.23 -3.39 0.16Disulfide, dimethyl 94.2 <298.2 383.0 -1.41 -1.45 0.04Bicyclo[2.2.1]-2-heptene 94.2 319.0 369.0 -1.12 -1.37 0.25Acetic acid, chloro- 94.5 335.2 462.5 -4.05 -3.76 0.29Fluorobenzene 96.1 <298.2 358.3 -0.98 -0.99 0.012-Furancarboxaldehyde 96.1 <298.2 434.9 -2.52 -2.44 0.081-Heptyne 96.2 <298.2 373.0 -1.37 -1.28 0.094-Methylcyclohexene 96.2 <298.2 376.0 -1.28 -1.31 0.03Methylenecyclohexane 96.2 <298.2 376.0 -1.28 -1.31 0.031-Ethylcyclopentene 96.2 <298.2 381.0 -1.33 -1.40 0.071-Methylcyclohexene 96.2 <298.2 383.0 -1.42 -1.44 0.02Ethene, 1,1-dichloro- 96.9 <298.2 304.9 -0.09 -0.10 0.01Ethene, 1,2-dichloro- 96.9 <298.2 328.2 -0.56 -0.47 0.09Ethene, 1,2-dichloro-, (Z)- 96.9 <298.2 328.2 -0.56 -0.47 0.09Ethene, 1,2-dichloro-, (E)- 96.9 <298.2 328.2 -0.35 -0.47 0.13cis-1,2-Dichloroethylene 96.9 <298.2 333.0 -0.60 -0.56 0.04Hexanenitrile 97.2 <298.2 436.8 -2.41 -2.53 0.122-Furanmethanol 98.1 <298.2 444.2 -3.08 -3.01 0.072,5-Furandione 98.1 326.0 475.2 -3.47 -3.52 0.054,4-Dimethyl-1-pentene 98.2 <298.2 346.0 -0.75 -0.78 0.03trans-4,4-Diemthyl-2-pentene 98.2 <298.2 350.0 -0.84 -0.85 0.013,3-Dimethyl-1-pentene 98.2 <298.2 351.0 -0.87 -0.87 0.002,4-Dimethyl-1-pentene 98.2 <298.2 355.0 -0.91 -0.94 0.032,3-Dimethyl-1-pentene 98.2 <298.2 357.0 -0.98 -0.98 0.00

70

2,4-Dimethyl-2-pentene 98.2 <298.2 357.0 -0.96 -0.97 0.01trans-1,2-Diemthylcyclopentane 98.2 <298.2 365.0 -1.08 -1.11 0.031-Heptene 98.2 <298.2 367.0 -1.14 -1.17 0.033-Heptene (cis-) 98.2 <298.2 368.9 -1.14 -1.20 0.06trans-3-Heptene 98.2 <298.2 369.0 -1.18 -1.20 0.022,3-Dimethyl-2-pentene 98.2 <298.2 371.0 -1.19 -1.23 0.04trans-2-Heptene 98.2 <298.2 371.0 -1.22 -1.24 0.022-Heptene (cis-) 98.2 <298.2 371.2 -1.18 -1.24 0.06cis-1,2-Dimethylcyclopentane 98.2 <298.2 372.0 -1.21 -1.24 0.031,2-Dimethylcyclopentane(cis-) 98.2 <298.2 372.7 -1.19 -1.25 0.06Methylcyclohexane 98.2 <298.2 374.0 -1.21 -1.27 0.06Ethylcyclopentane 98.2 <298.2 377.0 -1.28 -1.33 0.05Cycloheptane 98.2 <298.2 391.6 -1.53 -1.60 0.073-Penten-2-one, 4-methyl- 98.2 <298.2 403.2 -1.95 -1.83 0.13Cyclohexanone 98.2 <298.2 428.0 -2.20 -2.31 0.111,1-Dichloroethane 99.0 <298.2 330.2 -0.52 -0.51 0.02Ethane, 1,1-dichloro- 99.0 <298.2 330.6 -0.51 -0.51 0.00Ethane, 1,2-dichloro- 99.0 <298.2 356.7 -0.97 -0.97 0.00Acetic acid, cyano-, methylester 99.1 <298.2 473.7 -3.73 -3.27 0.461-Methyl-2-pyrrolidone 99.1 <298.2 475.2 -3.33 -3.27 0.06Cyclohexanamine 99.2 <298.2 407.2 -1.86 -1.98 0.122-Propenoic acid, ethyl ester 100.1 <298.2 372.6 -1.28 -1.26 0.02Methyl methacrylate 100.1 <298.2 373.2 -1.30 -1.27 0.032-Propenoic acid, 2-methyl-,methyl ester 100.1 <298.2 373.7 -1.28 -1.28 0.012,4-Pentanedione 100.1 <298.2 413.6 -2.40 -2.03 0.362,2-Dimethylpentane 100.2 <298.2 352.0 -0.87 -0.89 0.02Butane, 2,2,3-trimethyl- 100.2 <298.2 354.0 -0.86 -0.92 0.062,4-Dimethylpentane 100.2 <298.2 354.0 -0.89 -0.93 0.043,3-Dimethylpentane 100.2 <298.2 359.0 -0.97 -1.01 0.042-methylhexane 100.2 <298.2 363.0 -1.07 -1.09 0.023-Methylhexane 100.2 <298.2 365.0 -1.10 -1.13 0.033-Ethylpentane 100.2 <298.2 367.0 -1.12 -1.17 0.05Butane, 1-(ethenyloxy)- 100.2 <298.2 367.2 -1.18 -1.17 0.00heptane 100.2 <298.2 372.0 -1.24 -1.27 0.032-Pentanone, 4-methyl- 100.2 <298.2 389.7 -1.57 -1.58 0.01Methyl isobutyl ketone 100.2 <298.2 390.0 -1.60 -1.58 0.022-Hexanone 100.2 <298.2 400.2 -1.80 -1.79 0.01

71

Cyclohexanol 100.2 298.6 434.0 -2.96 -2.77 0.20Ethanamine, N,N-diethyl- 101.2 <298.2 362.2 -1.11 -1.07 0.041-Hexanamine 101.2 <298.2 406.0 -1.91 -2.00 0.09Acetic acid, 1-methylethylester 102.1 <298.2 361.8 -1.09 -1.06 0.03Acetic acid, propyl ester 102.1 <298.2 374.7 -1.34 -1.30 0.03Formic acid, butyl ester 102.1 <298.2 379.3 -1.41 -1.40 0.01Butanoic acid, 3-methyl- 102.1 <298.2 449.7 -3.22 -3.13 0.09Pentanoic acid 102.1 <298.2 459.3 -3.48 -3.37 0.11Diisopropyl ether 102.2 <298.2 341.0 -0.70 -0.70 0.00Propane, 2,2'-oxybis- 102.2 <298.2 341.7 -0.69 -0.71 0.02Propane, 1,1'-oxybis- 102.2 <298.2 363.2 -1.07 -1.10 0.03Butane, 1-ethoxy- 102.2 <298.2 365.5 -1.15 -1.14 0.012-Pentanol, 4-methyl- 102.2 <298.2 404.8 -2.14 -2.13 0.01Hexanol 102.2 <298.2 429.2 -2.95 -2.71 0.24Benzonitrile 103.1 <298.2 464.3 -2.98 -3.05 0.061,2-Ethanediamine, N-(2-aminoethyl)- 103.2 <298.2 480.2 -3.50 -3.86 0.362-Pyridinecarbonitrile 104.1 302.2 497.7 -3.17 -3.79 0.621-Pentanethiol 104.2 <298.2 399.8 -1.73 -1.79 0.06Styrene 104.2 <298.2 403.8 -2.06 -1.83 0.23Cyclooctatetraene 104.2 <298.2 416.0 -2.00 -2.07 0.07Benzene, ethenyl- 104.2 <298.2 418.2 -2.06 -2.11 0.051,5-Pentanediol 104.2 <298.2 512.2 -5.28 -4.89 0.38Ethanol, 2- (2-aminoethyl)amino 104.2 <298.2 517.0 -5.95 -5.11 0.84Benzaldehyde 106.1 <298.2 452.2 -3.76 -2.80 0.97Ethanol, 2,2'-oxybis- 106.1 <298.2 519.0 -4.97 -5.05 0.08Ethyl benzene 106.2 <298.2 409.4 -1.90 -1.95 0.05p-Xylene 106.2 <298.2 411.5 -1.94 -2.25 0.31m-Xylene 106.2 <298.2 412.3 -1.96 -2.00 0.03o-Xylene 106.2 <298.2 417.0 -2.06 -2.09 0.03Benzenemethanamine 107.2 <298.2 458.2 -3.05 -3.04 0.01Benzenamine, N-methyl- 107.2 <298.2 469.4 -3.21 -3.28 0.07Benzenamine, 2-methyl- 107.2 <298.2 473.5 -3.45 -3.36 0.09Benzenamine, 3-methyl- 107.2 <298.2 476.5 -3.39 -3.42 0.04Carbamic chloride, dimethyl- 107.5 <298.2 440.2 -2.58 -2.56 0.02Anisole 108.1 <298.2 427.0 -2.70 -2.29 0.41p-Cresol 108.1 <298.2 475.0 -3.81 -3.68 0.13Benzenemethanol 108.1 <298.2 478.5 -4.07 -3.77 0.30Hydrazine, phenyl- 108.1 <298.2 516.7 -4.46 -4.48 0.02

72

Pentanedinitrile, 2-methyl- 108.1 <298.2 536.2 -5.16 -4.65 0.51Hexanedinitrile 108.1 <298.2 568.2 -6.03 -5.41 0.62o-Cresol 108.1 304.0 464.0 -3.49 -3.47 0.02Phenol, 4-methyl- 108.1 308.7 475.1 -3.83 -3.76 0.071,3-Benzenediamine 108.1 336.7 558.2 -5.73 -5.74 0.014-vinyl-1-cyclohexene 108.2 <298.2 399.0 -1.74 -1.74 0.00Cyclohexene, 4-ethenyl- 108.2 <298.2 401.2 -1.67 -1.78 0.11Carbonochloridic acid, ethylester 108.5 <298.2 366.2 -1.52 -1.14 0.38Acetic acid, chloro-, methylester 108.5 <298.2 402.7 -1.98 -1.83 0.16Bromoethane 109.0 <298.2 311.6 0.33 -0.21 0.54Ethane, bromo- 109.0 <298.2 311.7 -0.20 -0.21 0.011,4-Benzenediol 110.1 445.5 560.2 -6.05 -6.96 0.902,5-Dimethyl-1,5-hexadiene 110.2 <298.2 407.0 -1.67 -1.92 0.25cis-Cyclooctene 110.2 <298.2 411.0 -2.01 -1.97 0.04Benzenethiol 110.2 <298.2 442.3 -2.58 -2.59 0.01Norcamphor 110.2 363.2 443.2 -2.76 -3.18 0.421,3-Dichloropropene 111.0 <298.2 379.0 -1.30 -1.37 0.071-Propene, 1,3-dichloro- 111.0 <298.2 385.2 -1.34 -1.49 0.151-Pentene, 2,4,4-trimethyl- 112.2 <298.2 374.2 -1.22 -1.29 0.07Propylcyclopentane 112.2 <298.2 376.0 -1.79 -1.31 0.481,1,3-Trimethylcyclopentane 112.2 <298.2 378.0 -1.28 -1.35 0.072-Pentene, 2,4,4-trimethyl- 112.2 <298.2 378.1 -1.31 -1.36 0.04Cycloheptanone 112.2 <298.2 392.0 -1.49 -1.61 0.12trans-1,4-Diemthylcyclohexane 112.2 <298.2 392.0 -1.53 -1.61 0.08trans-1,4-Dimethylcyclohexane 112.2 <298.2 392.6 -1.51 -1.62 0.111,1-Dimethylcyclohexane 112.2 <298.2 392.8 -1.51 -1.62 0.111,1-Dimethylcyclohexane 112.2 <298.2 393.0 -1.53 -1.63 0.10cis-1,3-Dimethylcyclohexane 112.2 <298.2 393.0 -1.56 -1.63 0.071-Octene 112.2 <298.2 394.0 -1.65 -1.69 0.044-Octene (trans) 112.2 <298.2 395.5 -1.62 -1.71 0.10cis-1,2-Dimethylcyclohexane 112.2 <298.2 396.7 -1.71 -1.70 0.01trans-1,2-Dimethylcyclohexane 112.2 <298.2 396.7 -1.58 -1.70 0.12cis-1,4-Dimethylcyclohexane 112.2 <298.2 397.0 -1.64 -1.70 0.06trans-1,2-Diemthylcyclohexane 112.2 <298.2 397.0 -1.60 -1.70 0.101,3-Dimethylcyclohexane 112.2 <298.2 397.7 -1.53 -1.72 0.18

73

trans-1,3-Dimethylcyclohexane 112.2 <298.2 397.7 -1.62 -1.72 0.10trans-1,3-Diemthylcyclohexane 112.2 <298.2 398.0 -1.64 -1.72 0.082-Octene (trans-) 112.2 <298.2 398.2 -1.65 -1.77 0.11cis-1,2-Dimethylcyclohexane 112.2 <298.2 403.0 -1.73 -1.82 0.09Propylcyclopentane 112.2 <298.2 404.2 -1.77 -1.86 0.08Ethylcyclohexane 112.2 <298.2 405.0 -1.77 -1.86 0.09Ethyl cyclohexane 112.2 <298.2 405.1 -1.76 -1.86 0.10Cyclooctane 112.2 <298.2 422.0 -2.14 -2.19 0.05Norborneol 112.2 413.2 449.2 -2.84 -4.08 1.23Chlorobenzene 112.6 <298.2 405.0 -1.80 -1.86 0.06Propane, 1,2-dichloro- 113.0 <298.2 368.7 -1.14 -1.18 0.041,2-Dichloropropane 113.0 <298.2 370.2 -1.20 -1.21 0.01Acetic acid, cyano-, ethyl ester 113.1 <298.2 483.2 -4.28 -3.50 0.782H-Azepin-2-one, hexahydro- 113.2 342.5 543.2 -5.66 -5.29 0.37Acetic acid, trifluoro- 114.0 <298.2 346.2 -0.83 -0.89 0.062,2,4-Trimethylpentane 114.2 <298.2 372.0 -1.20 -1.24 0.042,2-Dimethylhexane 114.2 <298.2 380.0 -1.36 -1.41 0.052,5-dimethylhexane 114.2 <298.2 382.0 -1.41 -1.45 0.042,2,3-Trimethylpentane 114.2 <298.2 383.0 -1.38 -1.45 0.073,3-Dimethylhexane 114.2 <298.2 385.0 -1.43 -1.50 0.07Pentane, 2,3,4-trimethyl- 114.2 <298.2 386.7 -1.43 -1.53 0.092,3,4-Trimethylpentane 114.2 <298.2 387.0 -1.45 -1.53 0.082,3,3-Trimethylpentane 114.2 <298.2 388.0 -1.46 -1.55 0.092-Methyl-3-ethylpentane 114.2 <298.2 388.8 -1.49 -1.57 0.092-Methyl-3-ethylpentane 114.2 <298.2 389.0 -1.51 -1.58 0.072-Methylheptane 114.2 <298.2 391.0 -1.57 -1.63 0.063-Methyl-3-ethylpentane 114.2 <298.2 391.0 -1.53 -1.62 0.094-Methylheptane 114.2 <298.2 391.0 -1.58 -1.63 0.053-Methylheptane (dl) 114.2 <298.2 392.0 -1.60 -1.65 0.05Octane 114.2 <298.2 399.2 -1.75 -1.80 0.062-Hexanone, 5-methyl- 114.2 <298.2 417.2 -2.15 -2.12 0.033-Heptanone 114.2 <298.2 420.2 -2.45 -2.20 0.262-Heptanone 114.2 <298.2 424.2 -2.28 -2.28 0.00Cyclohexanol, 2-methyl-, trans 114.2 <298.2 438.2 -2.79 -2.82 0.03Cyclohexanol, 2-methyl-, cis- 114.2 <298.2 438.2 -2.71 -2.82 0.113-Methylcyclohexanol (trans-) 114.2 <298.2 440.2 -3.11 -2.86 0.252-Oxepanone 114.2 <298.2 488.2 -3.74 -3.55 0.19Morpholine, 4-ethyl- 115.2 <298.2 411.7 -2.17 -1.99 0.171-Heptanamine 115.2 <298.2 429.2 -2.43 -2.48 0.06

74

Butanoic acid, 3-oxo-, methylester 116.1 <298.2 444.9 -2.92 -2.68 0.24N-Nitrosomorpholine 116.1 302.2 498.2 -4.31 -3.80 0.51Propanoic acid, 2-methyl-,ethyl ester 116.2 <298.2 383.3 -1.46 -1.47 0.00Acetic acid, 1-methylpropylester 116.2 <298.2 385.2 -1.64 -1.50 0.13Butanoic acid, ethyl ester 116.2 <298.2 394.7 -1.76 -1.69 0.07Butyl acetate 116.2 <298.2 398.0 -1.70 -1.76 0.06Acetic acid, butyl ester 116.2 <298.2 399.3 -1.81 -1.78 0.022-Pentanone, 4-hydroxy-4-methyl- 116.2 <298.2 441.1 -2.63 -2.90 0.27Heptanol 116.2 <298.2 449.2 -3.61 -3.14 0.47Indene 116.2 <298.2 456.0 -2.58 -2.87 0.29Butanoic acid, 2-ethyl- 116.2 <298.2 467.2 -3.59 -3.51 0.09Hexanoic acid 116.2 <298.2 478.4 -4.23 -3.79 0.441H-Indole 117.2 325.7 527.2 -4.78 -4.63 0.15Carbonic acid, diethyl ester 118.1 <298.2 399.2 -1.83 -1.78 0.052-Propanol, 1-propoxy- 118.2 <298.2 423.2 -2.64 -2.53 0.11Benzene, (1-methylethenyl)- 118.2 <298.2 438.6 -2.45 -2.52 0.073-Methylstyrene 118.2 <298.2 441.0 -2.64 -2.57 0.07Ethanol, 2-butoxy- 118.2 <298.2 441.6 -2.92 -2.96 0.044-Methylstyrene 118.2 <298.2 442.0 -2.63 -2.59 0.042-Methylstyrene 118.2 <298.2 444.0 -2.63 -2.63 0.00Benzene, 1-ethenyl-4-methyl- 118.2 <298.2 446.0 -2.61 -2.67 0.06trans-beta-methylstyrene 118.2 <298.2 448.0 -2.68 -2.72 0.042,4-Pentanediol, 2-methyl- 118.2 <298.2 471.2 -4.75 -3.74 1.011,6-Hexanediol 118.2 318.2 523.2 -6.17 -5.42 0.75Chloroform 119.4 <298.2 334.0 -0.60 -0.57 0.03Methane, trichloro- 119.4 <298.2 334.3 -0.57 -0.58 0.00Isopropylbenzene 120.2 <298.2 424.2 -2.22 -2.24 0.02Cumene 120.2 <298.2 426.0 -2.21 -2.27 0.06Propylbenzene 120.2 <298.2 432.2 -2.34 -2.41 0.07m-Ethyltoluene 120.2 <298.2 434.5 -2.38 -2.44 0.061-Ethyl-4-methylbenzene 120.2 <298.2 435.0 -2.41 -2.45 0.04Benzene, 1-ethyl-4-methyl- 120.2 <298.2 435.2 -2.39 -2.46 0.071-Ethyl-2-methylbenzene 120.2 <298.2 438.0 -2.48 -2.52 0.041,3,5-Trimethylbenzene 120.2 <298.2 438.2 -2.49 -2.51 0.02Benzene, 1-ethyl-2-methyl- 120.2 <298.2 438.4 -2.45 -2.52 0.071,2,4-Trimethylbenzene 120.2 <298.2 442.2 -2.57 -2.59 0.021,2,3-Trimethylbenzene 120.2 <298.2 449.0 -2.70 -2.73 0.03

75

Oxirane, phenyl- 120.2 <298.2 467.3 -3.39 -3.11 0.28Acetophenone 120.2 <298.2 475.0 -3.30 -3.27 0.03Ethanone, 1-phenyl- 120.2 <298.2 475.2 -3.27 -3.27 0.00Benzaldehyde, 4-methyl- 120.2 <298.2 477.7 -3.47 -3.33 0.14Pyridine, 5-ethyl-2-methyl- 121.2 <298.2 451.5 -2.71 -2.79 0.08Benzenamine, N,N-dimethyl- 121.2 <298.2 466.6 -3.02 -3.20 0.182,5-Dimethylaniline 121.2 <298.2 487.0 -3.80 -3.64 0.162,6-Dimethylaniline 121.2 <298.2 488.2 -3.75 -3.66 0.09Benzaldehyde, 2-hydroxy- 122.1 <298.2 470.2 -3.09 -3.52 0.43Trimethoxy silane 122.2 <298.2 354.2 -0.99 -0.93 0.05Benzene, ethoxy- 122.2 <298.2 443.0 -2.67 -2.63 0.042-Ethylphenol 122.2 <298.2 477.7 -3.68 -3.70 0.02Phenol, 2,4-dimethyl- 122.2 <298.2 484.1 -3.88 -3.84 0.04Benzeneethanol 122.2 <298.2 491.4 -3.93 -4.04 0.124-Ethylphenol 122.2 320.2 491.2 -4.29 -4.22 0.071,2-Benzenediamine, 3-methyl- 122.2 336.7 528.2 -6.12 -5.03 1.091,2-Benzenediamine, 4-methyl- 122.2 362.7 538.2 -6.07 -5.49 0.581,3-Benzenediamine, 4-methyl- 122.2 372.2 565.2 -6.64 -6.21 0.422,6-Diaminotoluene 122.2 378.0 533.0 -5.50 -5.43 0.071,3-Benzenediamine, 2-methyl- 122.2 379.2 533.2 -5.48 -5.44 0.04Benzene, nitro- 123.1 <298.2 484.0 -3.48 -3.46 0.02Benzenamine, 2-methoxy- 123.2 <298.2 497.2 -3.96 -3.87 0.09Phenol, 2-methoxy- 124.1 305.2 478.2 -3.85 -3.77 0.082-Butene, 1,4-dichloro-, (E)- 125.0 <298.2 425.7 -2.33 -2.29 0.04Cyclohexane, isocyanato- 125.2 <298.2 445.2 -2.86 -2.65 0.211-Nonene 126.2 <298.2 420.1 -2.14 -2.22 0.08iso-propylcyclohexane 126.2 <298.2 428.0 -2.21 -2.31 0.10Propylcyclohexane 126.2 <298.2 430.0 -2.27 -2.37 0.10Chlorotoluene 126.6 <298.2 431.0 -2.30 -2.37 0.073-Chlorotoluene 126.6 <298.2 434.2 -2.46 -2.43 0.03Benzene, 1-chloro-4-methyl- 126.6 <298.2 435.6 -2.44 -2.46 0.02alpha-chlorotoluene 126.6 <298.2 452.0 -2.76 -2.80 0.04benzyl chloride 126.6 <298.2 452.0 -2.80 -2.80 0.00Benzene, (chloromethyl)- 126.6 <298.2 452.2 -2.75 -2.80 0.05Butane, 1,4-dichloro- 127.0 <298.2 434.2 -2.25 -2.47 0.22o-Chloroaniline 127.6 <298.2 482.0 -3.50 -3.52 0.024-Chloroaniline 127.6 342.0 505.0 -4.50 -4.37 0.13

76

2-Propenoic acid, 2-methylpropyl ester 128.2 <298.2 405.2 -1.96 -1.89 0.072-Propenoic acid, butyl ester 128.2 <298.2 418.2 -2.13 -2.16 0.03Naphthalene 128.2 353.4 491.1 -3.94 -3.98 0.042,2,4,4-Tetramethylpentane 128.3 <298.2 396.0 -1.59 -1.68 0.092,2,5-Trimethylhexane 128.3 <298.2 397.0 -1.67 -1.73 0.062,2,4-Trimethylhexane 128.3 <298.2 400.0 -1.69 -1.79 0.102,4,4-Trimethylhexane 128.3 <298.2 400.0 -1.76 -1.79 0.032,2,3,4-Tetramethylpentane 128.3 <298.2 406.2 -1.77 -1.90 0.142,3,3-Trimethylhexane 128.3 <298.2 411.0 -1.83 -2.01 0.182,2,3,3-Tetramethylpentane 128.3 <298.2 413.4 -1.89 -2.04 0.154-Methyloctane 128.3 <298.2 415.0 -2.05 -2.11 0.062-Methyloctane 128.3 <298.2 416.0 -2.08 -2.13 0.053-Methyloctane 128.3 <298.2 417.4 -2.07 -2.16 0.093,3-Diethylpentane 128.3 <298.2 419.5 -2.00 -2.19 0.19Nonane 128.3 <298.2 424.0 -2.26 -2.31 0.052-Chlorophenol 128.6 <298.2 449.2 -2.87 -3.03 0.163-Chlorophenol 128.6 307.2 487.2 -3.45 -3.97 0.524-Chlorophenol 128.6 315.9 493.2 -3.87 -4.17 0.302-Propanol, 1,3-dichloro- 129.0 <298.2 449.2 -2.99 -3.06 0.07Quinoline 129.2 <298.2 510.3 -4.09 -4.02 0.07Bromochloromethane 129.4 <298.2 341.0 -0.71 -0.69 0.02Methane, bromochloro- 129.4 <298.2 341.2 -0.71 -0.69 0.02Butanoic acid, 3-oxo-, ethylester 130.1 <298.2 454.0 -2.97 -2.88 0.09Butanoic acid, 3-methyl-, ethylester 130.2 <298.2 408.2 -1.95 -1.96 0.01Butane, 1,1'-oxybis- 130.2 <298.2 413.4 -2.09 -2.09 0.001-Butanol, 3-methyl-, acetate 130.2 <298.2 415.7 -2.12 -2.11 0.01Acetic acid, pentyl ester 130.2 <298.2 422.4 -2.32 -2.25 0.072-Octanol 130.2 <298.2 453.2 -3.48 -3.20 0.281-Hexanol, 2-ethyl- 130.2 <298.2 457.8 -3.73 -3.30 0.432-Ethyl-1-hexanol 130.2 <298.2 458.0 -3.70 -3.31 0.39Octanol 130.2 <298.2 468.2 -3.95 -3.57 0.38Heptanoic acid 130.2 <298.2 495.4 -5.12 -4.18 0.94Ethene, trichloro- 131.4 <298.2 360.4 -1.03 -1.03 0.011,3,5-Trioxane, 2,4,6-trimethyl- 132.2 <298.2 397.5 -1.82 -1.71 0.11Ethanol, 2-ethoxy-, acetate 132.2 <298.2 429.6 -2.50 -2.40 0.10Cinnamaldehyde 132.2 <298.2 519.2 -4.09 -4.24 0.151,1,1-Trichloroethane 133.4 <298.2 347.2 -0.82 -0.80 0.02

77

1,1,2-Trichloroethane 133.4 <298.2 387.2 -1.51 -1.53 0.02Ethane, 1,1'-oxybis 2-methoxy- 134.2 <298.2 435.2 -2.40 -2.54 0.14t-Butylbenzene 134.2 <298.2 442.2 -2.54 -2.59 0.05Isobutylbenzene 134.2 <298.2 446.0 -2.56 -2.69 0.13Sec-Butylbenzene 134.2 <298.2 446.2 -2.62 -2.70 0.07Benzene, 1-methyl-3-(1-methylethyl)- 134.2 <298.2 448.3 -2.63 -2.72 0.09Benzene, 1-methyl-4-(1-methylethyl)- 134.2 <298.2 449.7 -2.70 -2.75 0.051-isopropyl-4-methylbenzene 134.2 <298.2 450.0 -2.69 -2.76 0.07Benzene, 1-methyl-2-(1-methylethyl)- 134.2 <298.2 451.3 -2.69 -2.79 0.09Benzene, 1,4-diethyl- 134.2 <298.2 454.2 -2.84 -2.86 0.02Benzene, 1,3-diethyl- 134.2 <298.2 454.3 -2.81 -2.86 0.05Butylbenzene 134.2 <298.2 456.2 -2.86 -2.92 0.06Benzene, 1,2-diethyl- 134.2 <298.2 457.2 -2.85 -2.92 0.08Benzene, 1-ethyl-2,3-dimethyl- 134.2 <298.2 467.2 -3.07 -3.12 0.04Ethanol, 2-(2-ethoxyethoxy)- 134.2 <298.2 469.2 -3.77 -3.58 0.181,2,3,5-Tetramethylbenzene 134.2 <298.2 471.1 -3.20 -3.19 0.011,2,3,4-Tetramethylbenzene 134.2 <298.2 478.2 -3.34 -3.34 0.001-Propanone, 1-phenyl- 134.2 <298.2 490.7 -3.69 -3.62 0.07Thiophene, tetrahydro-3-methyl-, 1,1-dioxide 134.2 <298.2 549.2 -5.01 -4.88 0.13Benzo(b)thiophene 134.2 304.0 493.0 -3.59 -3.70 0.11d-2-Carene 136.2 <298.2 440.0 -2.52 -2.55 0.03Α-Pinene 136.2 <298.2 428.2 -2.20 -2.31 0.11Bicyclo 3.1.1 hept-2-ene,2,6,6-trimethyl- 136.2 <298.2 428.7 -2.19 -2.32 0.13d-alpha-pinene 136.2 <298.2 429.0 -2.25 -2.33 0.08l-beta-pinene 136.2 <298.2 439.0 -2.42 -2.53 0.11Bicyclo 3.1.1 heptane, 6,6-dimethyl-2-methylene- 136.2 <298.2 439.2 -2.40 -2.53 0.13Myrcene 136.2 <298.2 440.2 -2.74 -2.58 0.16d-limonene 136.2 <298.2 449.0 -2.57 -2.73 0.16dl-limonene 136.2 <298.2 449.0 -2.60 -2.73 0.13l-limonene 136.2 <298.2 449.0 -2.61 -2.73 0.12Limonene 136.2 <298.2 449.2 -2.57 -2.73 0.16Limonene 136.2 <298.2 449.2 -2.88 -2.73 0.15Terpinolene 136.2 <298.2 459.2 -3.01 -2.94 0.07Benzoic acid, methyl ester 136.2 <298.2 472.2 -3.29 -3.23 0.06

78

2-Propylphenol 136.2 <298.2 498.2 -3.94 -4.16 0.22Camphene 136.2 324.0 432.0 -2.41 -2.61 0.20dl-camphene 136.2 324.0 432.0 -2.41 -2.61 0.20Butane, 2-bromo- 137.0 <298.2 364.4 -1.11 -1.11 0.012-Nitroaniline 138.1 344.4 557.2 -5.92 -5.60 0.323-Nitroaniline 138.1 387.0 579.0 -6.90 -6.48 0.42Benzenamine, 4-nitro- 138.1 420.2 605.2 -7.95 -7.27 0.68Isophorone 138.2 <298.2 487.0 -3.31 -3.52 0.21Ethanol, 2-phenoxy- 138.2 <298.2 518.2 -5.02 -4.66 0.36Naphthalene, decahydro- 138.3 <298.2 460.5 -2.50 -2.97 0.46Naphthalene, decahydro-, cis- 138.3 <298.2 460.5 -2.97 -2.97 0.00Naphthalene, decahydro-,trans- 138.3 <298.2 460.5 -2.78 -2.97 0.19Phenol, 2-nitro- 139.1 318.0 489.2 -3.81 -4.08 0.27Phenol, 4-nitro- 139.1 388.2 552.2 -7.25 -6.10 1.16Methyl-o-isopropylphosphonofluoridate 140.1 <298.2 420.2 -2.41 -2.18 0.23Phosphoric acid, trimethylester 140.1 <298.2 470.4 -2.94 -3.21 0.271-Decene 140.3 <298.2 443.2 -2.64 -2.71 0.07Cyclohexane, butyl- 140.3 <298.2 454.1 -2.75 -2.88 0.13Cyclodecane 140.3 <298.2 474.0 -3.13 -3.25 0.12Benzoyl chloride 140.6 <298.2 470.4 -3.02 -3.17 0.15Pentane, 1,5-dichloro- 141.0 <298.2 452.2 -2.81 -2.86 0.05Iodomethane 141.9 <298.2 315.6 -0.27 -0.27 0.00Methane, iodo- 141.9 <298.2 315.7 -0.26 -0.27 0.012-Propenoic acid, 2-methyl-,butyl ester 142.2 <298.2 433.2 -2.54 -2.47 0.071-Methylnaphthalene 142.2 307.2 513.2 -4.04 -4.16 0.122-Methylnaphthalene 142.2 307.6 514.3 -4.13 -4.19 0.072,7-Diemthyloctane 142.3 <298.2 433.0 -2.31 -2.48 0.172-Methylnonane 142.3 <298.2 440.0 -2.57 -2.64 0.07Decane 142.3 <298.2 447.0 -2.77 -2.80 0.03bis-2-chloroethylether 143.0 <298.2 451.0 -2.70 -2.84 0.14Ethane, 1,1'-oxybis 2-chloro- 143.0 <298.2 451.7 -2.68 -2.85 0.181-Naphthalenamine 143.2 322.2 574.0 -5.25 -5.79 0.552-Naphthalenamine 143.2 384.2 579.2 -6.46 -6.46 0.00beta-naphthylamine 143.2 385.0 579.0 -6.50 -6.46 0.041-Propanamine, N,N-dipropyl- 143.3 <298.2 429.2 -2.69 -2.41 0.271-Nonanamine 143.3 <298.2 475.4 -3.42 -3.51 0.09Propanoic acid, 2-methyl-, 2- 144.2 <298.2 421.8 -2.23 -2.23 0.00

79

methylpropyl esterButanoic acid, butyl ester 144.2 <298.2 440.7 -2.61 -2.65 0.04Octanoic acid 144.2 <298.2 512.2 -5.33 -4.56 0.771-Naphthol 144.2 369.2 552.2 -5.29 -6.01 0.712-Naphthol 144.2 395.2 559.2 -5.39 -6.40 1.01Nonanol 144.3 <298.2 488.2 -3.99 -4.03 0.04alpha,alpha,alpha-trifluorotoluene 146.1 <298.2 375.0 -1.30 -1.29 0.01Ethanedioic acid, diethyl ester 146.1 <298.2 458.9 -3.25 -3.01 0.241,2-Ethanediol, diacetate 146.1 <298.2 463.2 -3.98 -3.10 0.882-Pentanethiol, 2,4,4-trimethyl- 146.3 <298.2 428.7 -2.17 -2.35 0.17m-Dichlorobenzene 147.0 <298.2 445.0 -2.50 -2.65 0.15o-Dichlorobenznee 147.0 <298.2 454.0 -2.71 -2.83 0.12p-Dichlorobenzene 147.0 326.0 447.0 -3.02 -2.88 0.14Acetaldehyde, trichloro- 147.4 <298.2 371.0 -1.17 -1.22 0.05Trichloroacetaldehyde 147.4 <298.2 371.0 -1.20 -1.22 0.021,2,3-Trichloropropane 147.4 <298.2 429.2 -2.31 -2.33 0.02Trichlorohydrin 147.4 <298.2 430.0 -2.38 -2.38 0.00Propane, 1,2,3-trichloro- 147.4 <298.2 430.2 -2.30 -2.38 0.081,3-Isobenzofurandione 148.1 404.0 568.2 -6.15 -6.23 0.08Anethole 148.2 <298.2 508.2 -4.13 -4.01 0.121-Ethyl-3-isopropylbenzene 148.3 <298.2 465.0 -2.98 -3.09 0.111-Ethyl-4-isopropylbenzene 148.3 <298.2 470.0 -3.07 -3.19 0.12Pentylbenzene 148.3 <298.2 478.0 -3.36 -3.38 0.02Pentamethylbenzene 148.3 327.2 505.2 -4.01 -4.14 0.12Ethanol, 2,2',2''-nitrilotris- 149.2 <298.2 608.6 -8.31 -7.38 0.93Methyltrichlorosilane 149.5 <298.2 338.8 -0.64 -0.65 0.01Benzoic acid, ethyl ester 150.2 <298.2 485.2 -3.44 -3.53 0.09Acetic acid, phenylmethylester 150.2 <298.2 486.2 -3.62 -3.55 0.07Carvacrol 150.2 <298.2 511.2 -4.46 -4.39 0.07Oxirane, (phenoxymethyl)- 150.2 <298.2 516.2 -4.87 -4.20 0.66Ethanol, 2,2'- 1,2-ethanediylbis(oxy) bis- 150.2 <298.2 558.2 -5.75 -5.93 0.18Thymol 150.2 323.2 506.2 -4.45 -4.50 0.04Thujone 152.2 <298.2 476.2 -3.34 -3.29 0.05Benzoic acid, 2-hydroxy-,methyl ester 152.2 <298.2 496.1 -4.33 -4.20 0.13Pulegone 152.2 <298.2 497.2 -4.04 -3.74 0.30Bicyclo 2.2.1 heptan-2-one, 152.2 449.2 477.2 -3.05 -4.64 1.58

80

1,7,7-trimethyl-Benzene, 1-methoxy-2-nitro- 153.1 <298.2 550.2 -5.32 -4.92 0.41Carbon tetrachloride 153.8 <298.2 350.0 -0.80 -0.85 0.05Sulfuric acid, diethyl ester 154.2 <298.2 481.2 -3.40 -3.46 0.06Biphenyl 154.2 360.0 528.0 -4.90 -4.83 0.07Acenaphthylene, 1,2-dihydro- 154.2 366.6 552.2 -5.47 -5.55 0.08Acenaphthene 154.2 369.0 551.0 -5.37 -5.47 0.10Limonene Oxide 154.3 <298.2 449.2 -3.53 -2.73 0.80Cineole 154.3 <298.2 449.2 -3.05 -2.73 0.321-Undecene 154.3 <298.2 465.9 -3.17 -3.22 0.05Linalool 154.3 <298.2 470.2 -3.68 -3.50 0.18Citronellal 154.3 <298.2 481.2 -3.58 -3.48 0.10Terpineol 154.3 304.2 493.2 -3.83 -4.02 0.193-Cyclohexene-1-methanol,.alpha.,.alpha.,4-trimethyl- 154.3 306.2 490.7 -4.50 -4.00 0.51Iodoethane 156.0 <298.2 345.2 -0.75 -0.76 0.02N,N-Bis(2-chloroethyl)methylamine 156.1 <298.2 490.2 -3.64 -3.68 0.041-Ethylnaphthalene 156.2 <298.2 532.0 -4.60 -4.51 0.092-Ethylnaphthalene 156.2 <298.2 532.0 -4.93 -4.50 0.431,6-Dimethyl naphthalene 156.2 <298.2 537.2 -4.70 -4.61 0.092-Methyldecane 156.3 <298.2 462.0 -3.09 -3.13 0.04Undecane 156.3 <298.2 469.0 -3.28 -3.30 0.02Decanal 156.3 <298.2 482.2 -3.85 -3.58 0.27Benzoic acid, 2-chloro- 156.6 413.4 560.2 -6.05 -6.55 0.50Bromobenzene 157.0 <298.2 428.2 -2.26 -2.31 0.05Bromobenzene 157.0 <298.2 429.0 -2.26 -2.33 0.07Decylamine 157.3 <298.2 490.0 -3.90 -3.86 0.04Nonanoic acid 158.2 <298.2 527.7 -5.80 -4.93 0.868-Methyl-1-nonanol 158.3 <298.2 494.2 -4.55 -4.15 0.40Decanol 158.3 <298.2 503.2 -4.94 -4.39 0.55Mustard Gas 159.1 <298.2 489.2 -3.83 -3.66 0.17Propanedioic acid, diethylester 160.2 <298.2 473.2 -3.44 -3.33 0.11Benzene, cyclohexyl- 160.3 <298.2 513.3 -4.27 -4.09 0.182,5-Dichlorotoluene 161.0 <298.2 472.2 -3.16 -3.21 0.052,4-Dichlorotoluene 161.0 <298.2 473.2 -3.15 -3.23 0.082,6-Dichlorotoluene 161.0 <298.2 473.2 -3.16 -3.23 0.07Benzene, (dichloromethyl)- 161.0 <298.2 478.2 -3.19 -3.34 0.142,3-Dichlorotoluene 161.0 <298.2 481.2 -3.26 -3.40 0.143,4-Dichlorotoluene 161.0 <298.2 482.2 -3.26 -3.42 0.16

81

Benzenamine, 3,4-dichloro- 162.0 345.2 545.2 -4.88 -5.43 0.55Tabun 162.1 <298.2 513.2 -4.02 -4.14 0.12Ethanol, 2-(2-butoxyethoxy)- 162.2 <298.2 504.2 -4.53 -4.40 0.12Pyridine, 3-(1-methyl-2-pyrrolidinyl)-, (S)- 162.2 <298.2 520.2 -4.29 -4.24 0.051,3-Benzodioxole, 5-(1-propenyl)- 162.2 <298.2 525.2 -3.90 -4.36 0.46Benzene, 1,3-bis(1-methylethyl)- 162.3 <298.2 476.4 -3.27 -3.33 0.06Benzene, 1,4-bis(1-methylethyl)- 162.3 <298.2 483.5 -3.48 -3.48 0.001,2,4-Triethylbenzene 162.3 <298.2 491.0 -3.47 -3.67 0.20n-Hexylbenzene 162.3 <298.2 499.2 -3.86 -3.89 0.031-trans-5-trans-9-cis-cyclododecatriene 162.3 <298.2 504.0 -3.94 -3.89 0.05Hexamethyldisiloxane 162.4 <298.2 372.2 -1.24 -1.25 0.011-Chloronaphthalene 162.6 <298.2 536.2 -4.40 -4.59 0.192-Chloronaphthalene 162.6 333.2 529.2 -4.78 -4.74 0.042,4-Dichlorophenol 163.0 318.2 483.2 -3.91 -3.90 0.012,5-Dichlorophenol 163.0 330.2 484.2 -4.12 -4.03 0.092,3-Dichlorophenol 163.0 332.2 479.2 -4.10 -3.93 0.172,6-Dichlorophenol 163.0 340.2 492.2 -3.91 -4.25 0.343,4-Dichlorophenol 163.0 340.2 526.2 -4.63 -5.09 0.463,5-Dichlorophenol 163.0 341.2 506.2 -4.94 -4.58 0.36Acetic acid, trichloro- 163.4 330.7 469.7 -3.66 -3.70 0.04Eugenol 164.2 <298.2 526.2 -4.53 -4.77 0.244-Propylphenol 164.3 <298.2 505.2 -4.13 -4.26 0.14Chloropicrin 164.4 <298.2 385.0 -1.63 -1.48 0.15Methane, trichloronitro- 164.4 <298.2 385.2 -1.49 -1.48 0.01Tetrachloroethylene 165.8 <298.2 394.0 -1.60 -1.65 0.05Tetrachloroethene 165.8 <298.2 394.5 -1.61 -1.66 0.059H-Fluorene 166.2 388.0 568.2 -4.94 -6.00 1.061,1'-Bicyclohexyl 166.3 <298.2 511.2 -3.83 -4.04 0.219H-Carbazole 167.2 520.2 628.2 -6.84 -8.56 1.721,1,1,2-Tetrachloroethane 167.9 <298.2 403.7 -1.74 -1.84 0.10Ethane, 1,1,1,2-tetrachloro- 167.9 <298.2 403.7 -1.79 -1.84 0.051,1,2,2-Tetrachloroethane 167.9 <298.2 419.2 -2.17 -2.15 0.02Benzene, 1,3-dinitro- 168.1 363.2 570.2 -5.91 -5.86 0.06Diphenylmethane 168.2 <298.2 537.0 -4.81 -4.64 0.17Dibenzofuran 168.2 359.7 560.2 -5.45 -5.60 0.161-Dodecene 168.3 <298.2 487.0 -3.66 -3.71 0.05

82

Benzenamine, N-phenyl- 169.2 326.1 575.2 -5.96 -5.83 0.13Thiophosphoryl chloride 169.4 <298.2 398.2 -1.65 -1.73 0.07Benzene, 1,1'-oxybis- 170.2 <298.2 531.2 -4.51 -4.48 0.031,1'-Biphenyl -2-ol 170.2 332.2 559.2 -5.57 -5.78 0.22Dodecane 170.3 <298.2 489.0 -3.77 -3.77 0.00Naphthalene, 2-(1-methylethyl)- 170.3 <298.2 541.4 -5.15 -4.71 0.452,6-Dichlorobenzonitrile 172.0 361.2 543.2 -5.88 -5.23 0.64Acetic acid, 2-ethylhexyl ester 172.3 <298.2 472.2 -3.50 -3.34 0.171-Undecanol 172.3 <298.2 516.2 -5.39 -4.71 0.69Naphthalene, 1-nitro- 173.2 334.2 577.2 -6.19 -5.83 0.36Methane, dibromo- 173.8 <298.2 370.2 -1.22 -1.20 0.02Butanedioic acid, diethyl ester 174.2 <298.2 490.9 -4.22 -3.74 0.48Benzene, 2,4-diisocyanato-1-methyl- 174.2 <298.2 524.2 -4.96 -4.33 0.64Benzoic acid, butyl ester 178.2 <298.2 523.5 -4.87 -4.42 0.45Phenanthrene 178.2 373.2 613.2 -6.69 -6.92 0.23Anthracene 178.2 490.0 615.0 -8.40 -7.68 0.72Dodecahydrofluorene 178.3 <298.2 526.0 -4.20 -4.37 0.17Phosphoric triamide,hexamethyl- 179.2 <298.2 505.7 -4.20 -3.97 0.23cis-Stilbene 180.3 <298.2 579.7 -5.03 -5.61 0.57Benzene, 1-chloro-4-(trifluoromethyl)- 180.6 <298.2 411.7 -1.98 -1.99 0.001,2,4-Trichlorobenzene 181.5 <298.2 487.2 -3.22 -3.53 0.311,2,3-Trichlorobenzene 181.5 325.8 492.2 -3.31 -3.87 0.561,3,5-Trichlorobenzene 181.5 336.0 481.2 -3.50 -3.63 0.132,6-Dinitrotoluene 182.1 344.2 573.2 -6.10 -5.82 0.28Benzene, 2-methyl-1,3-dinitro- 182.1 344.2 573.2 -6.11 -5.78 0.34Diazene, diphenyl- 182.2 341.7 566.2 -6.31 -5.60 0.711,1-Diphenylethane 182.3 <298.2 545.8 -4.80 -4.83 0.043,3-Dimethylbiphenyl 182.3 <298.2 553.0 -5.40 -4.97 0.431-Tridecene 182.4 <298.2 506.0 -4.06 -4.17 0.112-Propenoic acid, 2-ethylhexylester 184.3 <298.2 486.7 -3.62 -3.67 0.05Dibenzothiophene 184.3 373.2 605.0 -5.59 -6.73 1.14Tridecane 184.4 <298.2 508.6 -4.12 -4.24 0.12(2-bromoethyl)benzene 185.1 <298.2 491.0 -3.49 -3.64 0.15Benzene, hexafluoro- 186.1 <298.2 353.4 -0.94 -0.90 0.041-Dodecanol 186.3 <298.2 532.2 -5.94 -5.11 0.83Ethane, 1,2-bis(2- 187.1 <298.2 505.2 -4.09 -4.09 0.00

83

chloroethoxy)-Ethane, 1,1,1-trichloro-2,2,2-trifluoro- 187.4 <298.2 319.3 -0.31 -0.33 0.02Ethane, 1,1,2-trichloro-1,2,2-trifluoro- 187.4 <298.2 320.9 -0.31 -0.36 0.051,2-Dibromoethane 187.9 <298.2 404.0 -1.70 -1.85 0.15Ethane, 1,2-dibromo- 187.9 <298.2 404.8 -1.82 -1.86 0.051,2-Dibromomethane 187.9 <298.2 440.0 -2.57 -2.56 0.01PCB-1 188.7 305.3 547.2 -4.69 -4.90 0.20PCB-3 188.7 351.1 564.2 -5.57 -5.68 0.11n-Octylbenzene 190.3 <298.2 537.2 -4.81 -4.81 0.011,4-Bromochlorobenzene 191.5 341.0 469.0 -3.46 -3.48 0.021,2,3,4-Tetrahydronaphthalene 192.2 <298.2 481.0 -3.26 -3.40 0.14Dimethyl phthalate 194.2 <298.2 555.0 -5.39 -5.09 0.301,2-Benzenedicarboxylic acid,dimethyl ester 194.2 <298.2 556.9 -5.65 -5.14 0.51Ethanol, 2,2'- oxybis(2,1-ethanediyloxy) bis- 194.2 <298.2 601.2 -9.08 -7.02 2.061,4-Benzenedicarboxylic acid,dimethyl ester 194.2 414.2 561.2 -4.87 -6.63 1.762,4,5-Trichlorotoluene 195.5 355.2 504.2 -3.87 -4.39 0.521-Tetradecene 196.4 <298.2 524.2 -4.69 -4.62 0.07Benzenamine, 4-(phenylazo)- 197.2 400.2 639.2 -8.72 -8.02 0.70Halothane 197.4 <298.2 323.4 -0.39 -0.40 0.012,3,6-Trichlorophenol 197.5 329.2 526.2 -5.48 -4.93 0.552,3,5-Trichlorophenol 197.5 331.2 521.1 -4.99 -4.83 0.162,4,5-Trichlorophenol 197.5 341.2 526.2 -4.59 -5.03 0.442,4,6-Trichlorophenol 197.5 343.2 518.2 -4.89 -4.82 0.073,4,5-Trichlorophenol 197.5 374.2 545.2 -5.48 -5.69 0.22Phenol, 2-methyl-4,6-dinitro- 198.1 359.8 651.2 -7.14 -8.21 1.07Methane, bromotrichloro- 198.3 <298.2 378.2 -1.28 -1.35 0.08Benzene, 1,1'-oxybis(methylene) bis- 198.3 <298.2 571.2 -5.86 -5.48 0.38Tetradecane 198.4 <298.2 527.0 -4.74 -4.70 0.04Acetic acid, (4-chloro-2-methylphenoxy)- 200.6 393.2 559.9 -8.10 -6.65 1.441,1,2,2,2-Pentachloroethane 202.3 <298.2 435.0 -2.22 -2.45 0.23Pentachloroethane 202.3 <298.2 435.2 -2.30 -2.45 0.15Fluoranthene 202.3 384.2 648.2 -7.91 -7.91 0.00Pyrene 202.3 429.2 677.2 -8.23 -8.60 0.38Ethane, 1,1,2,2-tetrachloro-1,2-difluoro- 203.8 299.2 366.2 -1.19 -1.15 0.04

84

Iodobenzene 204.0 <298.2 461.0 -2.88 -2.98 0.10Naphthalene, 1-bromo- 207.1 <298.2 554.2 -4.88 -4.99 0.11Benzoic acid, phenylmethylester 212.3 <298.2 596.7 -6.52 -6.06 0.46Pentadecane 212.4 <298.2 544.0 -5.25 -5.14 0.11Dodecanoic acid, methyl ester 214.4 <298.2 540.2 -5.25 -5.00 0.251,2,3,4-Tetrachlorobenzene 215.9 320.7 527.2 -4.28 -4.57 0.291,2,3,5-Tetrachlorobenzene 215.9 327.7 519.2 -4.01 -4.47 0.461,2,4,5-Tetrachlorobenzene 215.9 413.2 519.2 -5.17 -4.99 0.181,2,3-Propanetriol, triacetate 218.2 <298.2 532.2 -5.47 -4.69 0.78Benzene, decyl- 218.4 <298.2 571.2 -5.76 -5.68 0.08n-Decylbenzene 218.4 <298.2 596.2 -5.76 -6.29 0.531,2-Benzenedicarboxylic acid,diethyl ester 222.2 <298.2 568.2 -5.65 -5.47 0.18diethyl phthalate 222.2 <298.2 572.0 -5.70 -5.56 0.14PCB-11 223.1 302.2 595.2 -6.57 -5.95 0.62PCB-15 223.1 422.2 588.2 -7.32 -6.72 0.601-Hexadecene 224.4 <298.2 558.1 -5.45 -5.50 0.05Hexadecane 226.5 <298.2 560.0 -5.48 -5.56 0.082-Butenedioic acid (Z)-,dibutyl ester 228.3 <298.2 554.2 -6.07 -5.29 0.78Benzanthracene 228.3 433.0 711.0 -9.56 -9.85 0.29Benzo[a]anthracene 228.3 433.2 711.2 -9.56 -9.86 0.30Triphenylene 228.3 472.2 711.2 -8.65 -9.74 1.09Chrysene 228.3 529.2 721.2 -11.25 -10.71 0.54m-Dibromobenzene 235.9 <298.2 491.0 -3.24 -3.61 0.37p-Dibromobenzene 235.9 360.0 492.0 -3.67 -4.05 0.38Propane, 1,2-dibromo-3-chloro- 236.3 <298.2 469.2 -3.10 -3.19 0.08Heptadecane 240.5 <298.2 573.2 -6.51 -5.93 0.58Heptadecane 240.5 <298.2 575.0 -6.53 -5.97 0.56n-Dodecylbenzene 246.4 <298.2 573.2 -7.16 -5.80 1.36Benzene, dodecyl- 246.4 <298.2 601.2 -7.16 -6.47 0.69Benzene, 1-bromo-4-phenoxy- 249.1 <298.2 583.3 -5.69 -5.69 0.00Pentachlorobenzene 250.3 359.2 550.2 -5.01 -5.37 0.36Benzopyrene 252.3 449.0 768.0 -11.20 -11.24 0.04Benzo[a]pyrene 252.3 450.2 768.2 -11.16 -11.41 0.25Benzo[e]pyrene 252.3 451.2 765.2 -11.14 -11.34 0.20Benzo[k]fluoranthene 252.3 490.2 753.2 -11.88 -11.19 0.69Methane, tribromo- 252.7 <298.2 422.3 -2.13 -2.19 0.06Bromoform 252.7 <298.2 423.0 -2.12 -2.21 0.09

85

n-Octadecane 254.5 301.0 589.0 -6.65 -6.44 0.21Ethane, 1,2-dibromo-1,1,2,2-tetrafluoro- 259.8 <298.2 320.5 -0.35 -0.35 0.00Benzene, tridecyl- 260.5 <298.2 619.2 -7.76 -6.99 0.781,3-Butadiene, 1,1,2,3,4,4-hexachloro- 260.8 <298.2 488.2 -3.52 -3.57 0.05Phosphoric acid tributyl ester 266.3 <298.2 562.2 -6.79 -5.55 1.24Phenol, pentachloro- 266.3 447.2 582.7 -6.83 -7.06 0.23PCP 266.3 463.0 583.0 -7.70 -7.19 0.51VX 267.4 <298.2 573.2 -6.02 -5.67 0.35Methane, diiodo- 267.8 <298.2 455.2 -2.79 -2.86 0.07Nonadecane 268.5 305.0 603.0 -7.19 -6.97 0.221,3-Cyclopentadiene,1,2,3,4,5,5-hexachloro- 272.8 <298.2 512.2 -4.09 -4.06 0.02Indeno 1,2,3-cd pyrene 276.3 436.8 809.2 -12.87 -12.31 0.55Dibutyl phthalate 278.4 <298.2 613.0 -7.00 -6.70 0.301,2-Benzenedicarboxylic acid,dibutyl ester 278.4 <298.2 613.2 -7.00 -6.71 0.309,12-Octadecadienoic acid(Z,Z)- 280.5 <298.2 638.4 -8.93 -7.85 1.089-Octadecenoic acid (Z)- 282.5 317.2 633.2 -9.13 -8.27 0.86Eicosane 282.6 310.0 617.0 -7.69 -7.54 0.15Metolachlor 283.8 <298.2 555.2 -7.37 -5.21 2.16Hexachlorobenzene 284.8 503.2 605.2 -7.64 -7.21 0.43Hexachlorobenzene 284.8 504.0 598.0 -5.60 -7.05 1.45Cyclohexane, 1,2,3,4,5,6-hexachloro-, 290.8 385.7 596.6 -6.25 -6.72 0.47Parathion 291.3 <298.2 648.2 -7.88 -7.43 0.45Benzene, pentachloronitro- 295.3 417.2 601.2 -7.17 -6.98 0.18Octamethyltetrasiloxane 296.6 <298.2 449.2 -2.85 -2.73 0.111,2,4,5-Tetrabutylbenzene 302.6 <298.2 470.0 -3.18 -3.38 0.20Butyl benzyl phthalate 312.4 <298.2 643.0 -7.96 -7.38 0.59Decanedioic acid, dibutyl ester 314.5 <298.2 617.7 -8.20 -7.15 1.05Hexanedioic acid, dihexylester 314.5 <298.2 617.7 -8.41 -7.15 1.26DDE 318.0 362.2 609.2 -8.09 -6.93 1.16p,p'-DDD 320.1 382.7 623.2 -8.75 -7.62 1.13Tricosane 324.6 321.0 653.0 -9.41 -9.07 0.34Methane, tetrabromo- 331.6 363.3 463.2 -3.44 -3.36 0.08DCPA 332.0 429.2 643.2 -8.47 -8.74 0.27Benfluralin 335.3 339.2 643.2 -7.05 -8.06 1.02

86

Hexanedioic acid, bis(2-ethylhexyl) ester 370.6 <298.2 690.2 -8.94 -9.20 0.26Decamethylcyclopentasiloxane 370.8 <298.2 483.2 -3.57 -3.44 0.12Heptachlor 373.3 368.7 583.2 -6.26 -6.27 0.00Dieldrin 380.9 499.2 603.2 -8.10 -7.87 0.231,2-Benzenedicarboxylic acid,bis(2-ethylhexyl) est 390.6 <298.2 657.2 -7.88 -8.09 0.21Octacosane 394.8 338.0 705.0 -11.09 -11.67 0.58Octachlorodibenzo-p-dioxin 459.8 603.2 783.2 -14.95 -13.12 1.83

87

APPENDIX C: RESULTS OF THE OCTANOL-AIR PARTITION COEFFICIENT

ESTIMATIONS

Table C.1 Chemical Name, Molecular Weight, Boiling Point (Kelvin), Experimental and

Predicted log Octanol-Air Partition Coefficient, and Absolute Error in Prediction.

Exper PredChemical Name MW log Koa BP (K) log Koa AEMethyl formate 60.1 1.75 304.9 1.99 0.242-Methylbuta-1,3-diene 68.1 2.06 307.2 2.03 0.03Diethyl ether 74.1 2.19 307.8 2.04 0.151-Pentene 70.1 1.93 308.2 2.04 0.112-Monochloropropane 78.5 2.08 308.9 2.05 0.03Pentane 72.2 1.96 309.3 2.06 0.10Bromoethane 109.0 2.11 311.7 2.10 0.01Dichloromethane 84.9 2.27 313.2 2.12 0.15Iodomethane 141.9 2.16 315.7 2.16 0.00Allyl chloride 76.5 1.67 318.3 2.20 0.53Carbon disulphide 76.1 2.28 319.2 2.22 0.06Chloropropane 78.5 2.24 319.7 2.23 0.01trans-1,2-Dichloroethene 96.9 1.95 320.7 2.24 0.29Propanal 58.1 3.02 321.2 2.25 0.77Ethyl formate 74.1 2.19 327.2 2.35 0.16cis-1,2-Dichloroethene 96.9 2.56 328.2 2.36 0.20Methyl Tertiary Butyl Ether 88.1 2.58 328.4 2.37 0.21Acetone 58.1 2.31 328.7 2.37 0.06Methyl acetate 74.1 2.31 330.2 2.40 0.091,1-Dichloroethane 99.0 2.41 330.6 2.40 0.01Acetonitrile 41.1 2.31 332.8 2.44 0.13Trichloromethane 119.4 2.80 335.2 2.48 0.32Hex-1-ene 84.2 2.41 336.2 2.51 0.10Tetrahydrofuran 72.1 2.86 338.2 2.53 0.33Methanol 32.0 2.88 338.2 2.84 0.04Bromochloromethane 129.4 2.67 341.0 2.58 0.09Di-isopropyl ether 102.2 2.66 341.7 2.60 0.06

88

Hexane 86.2 2.40 341.9 2.61 0.212,2-Dichloropropane 113.0 2.30 342.2 2.60 0.30Iodoethane 156.0 2.59 345.2 2.65 0.061,1,1-Trichloroethane 133.4 2.70 347.2 2.69 0.01Butanal 72.1 3.39 348.0 2.71 0.681,1-Dichloropropene 111.0 2.51 349.7 2.73 0.22Butylamine 73.1 3.61 350.2 2.81 0.80Tetrachloromethane 153.8 2.79 350.2 2.74 0.05Ethyl acetate 88.1 2.70 350.3 2.75 0.05Acrylnitrile 53.1 2.28 350.5 2.74 0.46Chlorobutane 106.6 2.72 351.2 2.76 0.04Teramethyl tin 178.9 2.62 351.2 2.76 0.14Ethanol 46.1 3.25 351.5 3.05 0.202-Butanone 72.1 2.71 352.7 2.78 0.07Benzene 78.1 2.78 353.2 2.79 0.01Hexafluorobenzene 186.1 2.11 353.4 2.79 0.68Cyclohexane 84.2 2.74 353.9 2.80 0.06Propyl formate 88.1 2.66 354.1 2.82 0.16N-Methylpyrrolidine 85.1 3.64 354.2 2.81 0.832-Propanol 60.1 3.41 355.6 3.07 0.34t-Butanol 74.1 3.50 355.6 3.03 0.47Cyclohexene 82.2 2.83 356.1 2.84 0.011,2-Dichloroethane 99.0 2.78 356.2 2.85 0.07Fluorobenzene 96.1 2.84 357.9 2.87 0.03Pentafluorobenzene 168.1 2.54 358.2 2.88 0.33Pyrrolidine 71.1 4.07 359.7 2.98 1.09Trichloroethene 131.4 2.99 360.4 2.92 0.07Tetrahydropyran 86.1 3.22 361.2 2.96 0.26Isopropyl acetate 102.1 2.93 361.8 2.95 0.021,4-Difluorobenzene 114.1 2.93 362.2 2.95 0.02Dipropyl ether 102.2 2.97 363.2 2.99 0.02Dichlorobromomethane 163.8 2.97 363.2 2.97 0.00Methyl Acrylonitrile 67.1 2.60 363.5 2.97 0.373-Methyl-2-butanone 86.1 3.04 367.5 3.05 0.011,2-Dichloropropane 113.0 2.96 368.7 3.07 0.11Dibromomethane 173.8 3.07 370.2 3.09 0.02Propionitrile 55.1 2.69 370.3 3.10 0.411-Propanol 60.1 3.71 370.4 3.40 0.31

89

Heptane 100.2 2.95 371.6 3.15 0.20Ethyl Propionate 102.1 3.15 372.3 3.15 0.002-Butanol 74.1 3.85 372.7 3.40 0.45Methyl methacrylate 100.1 3.08 373.2 3.16 0.08Methylcyclohexane 98.2 3.05 374.1 3.17 0.12Nitromethane 61.0 2.53 374.3 3.17 0.64Propyl acetate 102.1 3.17 374.7 3.19 0.021,4-Dioxane 88.1 3.18 374.7 3.18 0.003-Pentanone 86.1 3.20 375.1 3.19 0.012-Pentanone 86.1 3.19 375.4 3.20 0.012-Propanenitrile 69.1 2.87 377.2 3.22 0.35Piperidine 85.2 4.04 379.5 3.34 0.702-Methyl-1-propanol 74.1 3.93 381.2 3.58 0.35Dipropyalmine 101.2 3.59 383.2 3.43 0.16Toluene 92.1 3.31 383.8 3.34 0.03cis-1,3-Dichloropropene 111.0 3.75 385.2 3.38 0.37trans-1,3-Dichloropropene 111.0 3.28 385.2 3.38 0.101,1,2-Trichloroethane 133.4 3.40 387.0 3.41 0.01Nitroethane 75.1 2.88 387.2 3.41 0.53Pyridine 79.1 4.20 388.4 3.43 0.774-Methyl-2-pentanone 100.2 3.30 389.7 3.47 0.17Isobutyl acetate 116.2 3.45 389.7 3.48 0.03Ethyl Methacrylate 114.1 3.34 390.2 3.48 0.14Butyronitrile 69.1 3.12 390.8 3.48 0.36Acetic Acid 60.1 4.31 391.2 3.87 0.441-Butanol 74.1 4.19 391.2 3.81 0.38Dibromochloromethane 208.3 3.59 393.2 3.52 0.07Oct-1-ene 112.2 3.35 394.2 3.58 0.23Tetrachloroethene 236.7 3.48 394.5 3.55 0.07Ethyl butanoate 116.2 3.56 394.7 3.58 0.02Di-isobutyl ether 130.2 3.40 396.2 3.62 0.22Octane 114.2 3.35 398.8 3.68 0.33Butyl acetate 116.2 3.65 399.2 3.67 0.022-Hexanone 100.2 3.68 400.2 3.68 0.002-Picoline 93.1 4.30 402.2 3.69 0.612-Chloroethanol 80.5 4.30 402.2 4.02 0.281,1,1,2-Tetrachloroethane 167.8 3.97 403.7 3.73 0.24Cyclopentanone 84.1 3.67 403.7 3.72 0.05

90

1-Nitropropane 89.1 3.25 404.2 3.74 0.49Isopentanol 88.1 4.52 404.2 4.05 0.47Hexanal 100.2 4.41 404.2 3.77 0.641,2-Dibromoethane 187.9 3.69 404.8 3.75 0.06Chlorobenzene 112.6 3.31 404.9 3.74 0.43Ethyl benzene 106.2 3.74 409.4 3.84 0.101-Pentanol 88.2 4.69 411.2 4.22 0.47p-Xylene 106.2 3.79 411.5 3.87 0.08o-Xylene 106.2 3.91 411.7 3.88 0.03m-Xylene 106.2 3.78 412.3 3.89 0.11Dibutyl ether 130.2 3.89 413.4 3.98 0.09Pentanonitrile 83.1 3.60 414.2 3.95 0.35Isopentyl acetate 130.2 3.94 415.2 3.99 0.05Styrene 104.2 3.92 418.2 4.00 0.081,1,2,2-Tetrachloroethane 167.8 4.30 419.7 4.05 0.25Non-1-ene 126.2 3.83 420.1 4.11 0.28Pentyl acetate 130.2 4.12 422.4 4.14 0.02Bromoform 252.7 4.23 423.2 4.10 0.132-Heptanone 114.2 4.15 424.2 4.17 0.02Isopropylbenzene 120.2 3.98 424.2 4.13 0.154-Bromofluorobenzene 175.0 4.11 424.7 4.13 0.02cis-1,4-Dichloro-2-butene 125.0 4.04 425.2 4.17 0.13trans-1,4-Dichloro-2-butene 125.0 4.15 425.7 4.18 0.03Tricyclene 136.2 3.87 425.7 4.15 0.28Dimethylformamide 73.1 4.38 426.2 4.17 0.21Anisole 108.1 4.01 426.9 4.18 0.17N-Nitrosodimethylamine 74.1 3.72 427.2 4.19 0.46Bromobenzene 157.0 4.08 428.2 4.20 0.12alpha-Pinene 136.2 3.75 428.2 4.20 0.451,2,3-Trichloropropane 147.4 4.52 430.2 4.27 0.251-Hexanol 102.2 5.18 431.2 4.64 0.542-Chlorotoluene 126.6 4.11 432.2 4.28 0.17Camphene 136.2 4.04 432.2 4.28 0.24Propylbenzene 120.2 4.09 432.2 4.30 0.21Pentachloroethane 202.3 3.89 433.0 4.31 0.42Cyclohexanol 100.2 5.18 434.0 4.65 0.534-Chlorotoluene 126.6 4.15 435.2 4.34 0.19Hexanonitrile 97.2 4.08 436.8 4.42 0.34

91

1,3,5-Trimethylbenzene 120.2 4.18 437.9 4.40 0.22Dimethylacetamide 87.1 5.33 438.2 4.41 0.92beta-Pinene 136.2 3.68 439.2 4.42 0.741,2,4-Trimethylbenzene 120.2 4.20 442.2 4.48 0.28tert-Butylbenzene 134.2 4.18 442.2 4.48 0.31N-Nitroso-methyl-ethylamine 88.1 3.85 443.2 4.53 0.683-Carene 136.2 3.80 443.2 4.50 0.70Octanal 128.2 5.36 444.2 4.61 0.75Hexyl acetate 144.2 4.58 444.7 4.62 0.04sec-Butylbenzene 134.2 4.20 446.2 4.59 0.381,3-Dichlorobenzene 147.0 4.30 446.2 4.56 0.261,4-Dichlorobenzene 147.0 4.46 446.2 4.56 0.10alpha-Terpinene 80.1 3.90 448.2 4.61 0.71p-Isopropyltoluene 134.2 4.54 449.7 4.63 0.09N-Nitrosodiethylamine 102.1 4.04 450.2 4.69 0.65Limonene 136.2 4.04 451.2 4.67 0.621,2-Dichlorobenzene 147.0 4.36 453.2 4.71 0.35Butylbenzene 134.2 4.34 456.2 4.81 0.47gamma-Terpinene 80.1 4.28 456.2 4.78 0.50Aniline 93.1 4.48 457.2 4.93 0.45Dipentylether 158.3 4.80 461.2 5.02 0.22Hexachloroethane 236.7 4.47 462.2 4.89 0.42Dimethyl sulfoxide 78.1 4.96 463.2 4.91 0.05Benzonitrile 103.1 4.46 464.2 4.93 0.47Octan-1-ol 128.2 6.03 468.2 5.45 0.581,2-Dibromo-3-Chloropropane 236.3 4.56 469.2 5.08 0.52o-Toluidine 107.2 4.66 473.4 5.26 0.60Decafluorobiphenyl 334.1 4.54 479.2 5.25 0.70N-Nitrosodipropylamine 130.2 4.30 479.2 5.34 1.041,3,5-Trichlorobenzene 181.5 4.85 481.2 5.29 0.441,2,4-Trichlorobenzene 181.5 4.95 486.7 5.41 0.46Hexachlorobutadiene 260.8 4.58 488.2 5.45 0.87Naphthalene 128.2 5.19 491.1 5.50 0.311,2,3-Trichlorobenzene 181.5 5.19 491.7 5.51 0.321,4-Dibromobenzene 235.9 5.21 492.2 5.52 0.31N-Nitrosodibutylamine 158.2 4.81 507.2 6.01 1.202-Methylnaphthalene 142.2 5.11 514.2 6.00 0.881,2,4,5-Tetrachlorobenzene 215.9 5.63 517.7 6.07 0.44

92

1,2,3,5-Tetrachlorobenzene 215.9 5.55 519.2 6.11 0.561,2,3,4-Tetrachlorobenzene 215.9 5.64 527.2 6.28 0.642-Chloronaphthalene 162.6 5.80 529.2 6.33 0.53Biphenyl 154.2 6.15 529.2 6.33 0.181-Chloronaphthalene 162.6 5.80 532.2 6.39 0.59Hexamethylbenzene 162.3 6.31 536.6 6.49 0.18PCB-1 188.7 6.65 547.2 6.72 0.07Pentachlorobenzene 250.3 6.49 550.2 6.79 0.30Acenaphthene 154.2 6.31 552.2 6.84 0.53PCB-2 188.7 6.82 558.2 6.97 0.152,7-Dichloronaphthalene 197.1 6.70 558.2 6.97 0.27alpha-Hexachlorocyclohexane 290.8 7.25 561.2 7.04 0.211,4-Dichloronapthalene 197.1 6.78 561.2 7.04 0.26PCB-3 188.7 6.80 564.2 7.11 0.31Fluorene 166.2 6.79 568.2 7.20 0.411,2-Dichloronapthalene 197.1 6.89 569.7 7.23 0.34Diphenylamine 169.2 7.64 575.2 7.53 0.11t-Stilbene 180.2 7.48 579.7 7.50 0.02Heptachlor 373.3 7.64 583.2 7.54 0.101-Chlorodibenzo-p-dioxin 218.6 7.86 589.2 7.68 0.18PCB-15 223.1 7.68 590.2 7.70 0.02PCB-11 223.1 7.90 595.2 7.81 0.09gamma-Hexachlorocyclohexane 290.8 7.85 596.2 7.84 0.01Hexachlorobenzene 284.8 7.38 598.2 7.88 0.50Dieldrin 380.9 8.90 603.2 8.00 0.901,4,6,7-Tetrachloronapthalene 266.0 8.13 604.2 8.02 0.111-Hexadecanol 242.5 9.90 607.2 9.00 0.90p,p'-DDE 318.0 9.68 609.2 8.18 1.50Anthracene 178.2 7.55 613.1 8.23 0.68Phenanthrene 178.2 7.57 613.2 8.23 0.66p,p'-DDD 320.1 10.10 623.2 8.55 1.55Oxychlordane 423.8 8.39 626.2 8.53 0.14PCB-49 292.0 8.39 633.2 8.70 0.314,4'-Dibromodiphenylether 328.0 8.60 634.2 8.77 0.171-Eicosanol 298.6 12.06 645.2 10.15 1.912,7-Dichlorodibenzo-p-dioxin 253.1 8.36 647.2 9.03 0.67Fluoranthene 202.3 8.88 648.2 9.05 0.172,8-Dichlorodibenzo-p-dioxin 253.1 8.36 656.2 9.24 0.88

93

Pyrene 202.3 8.80 677.2 9.74 0.941,2,3,4-Tetrachlorodibenzo-p-dioxin 322.0 9.70 692.2 10.10 0.40Benzo[a]anthracene 228.3 10.80 710.8 10.55 0.25Triphenylene 228.3 10.63 711.2 10.56 0.072,3,7,8-Tetrachlorodibenzofuran 306.0 10.02 711.5 10.57 0.552,3,7,8-Tetrachlorodibenzo-p-dioxin 322.0 10.05 720.2 10.78 0.73Chrysene 228.3 10.63 721.2 10.81 0.181,2,3,4,7,-Pentachlorodibenzo-p-dioxin 356.4 10.67 738.2 11.22 0.552,3,4,7,8-Pentachlorodibenzofuran 340.4 10.37 738.2 11.22 0.85Benzo[k]fluoranthene 252.3 11.18 753.2 11.59 0.411,2,3,4,7,8-Hexachlorodibenzo-p-dioxin 390.9 11.11 761.2 11.79 0.681,2,3,6,7,8-Hexachlorodibenzofuran 374.9 10.78 761.2 11.79 1.011,2,3,4,7,8-Hexachlorodibenzofuran 374.9 10.77 761.2 11.79 1.02Benzo[e]pyrene 252.3 11.13 765.2 11.89 0.76Benzo[a]pyrene 252.3 10.77 768.2 11.96 1.19Perlyene 252.3 11.70 770.2 12.01 0.311,2,3,4,6,7,8-Heptachlorodibenzofuran 409.3 11.17 780.2 12.26 1.091,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin 425.3 11.42 780.4 12.27 0.85Dibenz[a,h]anthracene 278.4 13.91 808.2 12.96 0.95

94

APPENDIX D: RESULTS OF THE AIR-WATER PARTITION COEFFICIENT

ESTIMATIONS FOR NON-IONIZABLE COMPOUNDS AND THOSE WITH

AQUEOUS SOLUBILITIES OF LESS THAN 50%

Table D.1 Chemical Name, Molecular Weight, Boiling Point (Kelvin), Experimental and

Predicted log Air-Water Partition Coefficient, and Absolute Error in Prediction for Non-

ionizable Compounds and those with Aqueous Solubilities of Less than 50%.

Exper PredName MW Tb (K) log Kaw log Kaw AEAcrylonitrile* 53.1 350.45 -2.25 -1.79 0.46Propionitrile* 55.1 370.25 -2.82 -2.05 0.77Propanal* 58.1 321.15 -2.52 -1.85 0.67Nitromethane* 61.0 374.25 -2.93 -2.45 0.48Dimethyl sulfide 62.1 310.45 -1.18 -0.12 1.06Ethyl mercaptan 62.1 308.25 -0.73 -0.44 0.29Pyrrole 67.1 402.85 -3.13 -2.98 0.16Furan 68.1 304.65 -0.66 -0.56 0.102-Methyl-1,3-butadiene 68.1 307.15 0.50 0.71 0.221,4-Pentadiene 68.1 299.15 0.69 1.46 0.77Cyclopentene 68.1 317.35 0.42 -0.07 0.49cis-2-Pentene 70.1 309.45 0.96 0.81 0.16trans-2-Pentene 70.1 309.45 0.97 0.81 0.172-Methyl-2-butene 70.1 311.65 0.96 0.69 0.27Cyclopentane 70.1 322.45 0.89 0.04 0.841-Pentene 70.1 308.15 1.21 1.07 0.142-Methyl-1-butene 70.1 304.35 1.25 1.03 0.22Isobutyraldehyde* 72.1 337.65 -2.13 -1.74 0.392-Butanone* 72.1 352.65 -2.63 -2.01 0.63Butanal 72.1 347.95 -2.33 -1.79 0.532-Methylbutane 72.2 300.95 1.76 0.94 0.82Pentane 72.2 309.15 1.71 1.13 0.58Methyl acetate* 74.1 365.15 -2.33 -2.26 0.072-Butanol* 74.1 372.65 -3.43 -2.55 0.88(+)2-Butanol* 74.1 372.65 -3.43 -2.55 0.88Isobutyl alcohol* 74.1 380.95 -3.40 -2.54 0.86

95

2-Methyl-1-propanol* 74.1 380.95 -3.40 -2.54 0.86Methyl isopropyl ether 74.1 303.85 -1.43 -0.99 0.44Butyl alcohol 74.1 391.15 -3.44 -2.59 0.85Diethyl ether 74.1 307.65 -1.30 -0.87 0.43Methyl propyl ether 74.1 312.25 -1.22 -0.94 0.27Peroxyacetic acid 76.1 383.15 -4.06 -4.83 0.77Dimethoxymethane* 76.1 315.15 -2.15 -3.01 0.861-Propanethiol 76.2 340.95 -0.48 -0.47 0.013-Chloropropylene 76.5 318.25 -0.35 -0.01 0.34Benzene 78.1 353.15 -0.64 -0.62 0.032-Chloropropane 78.5 308.85 -0.15 0.03 0.171-Chloroproprane 78.5 319.65 -0.27 0.04 0.311-Chloropropane 78.5 319.15 -0.27 0.05 0.321,4-Cyclohexadiene 80.1 358.65 -0.40 -0.26 0.131,5-Hexadiene 82.1 332.55 0.76 1.12 0.362,3-Dimethyl-1,3-Butadiene 82.2 341.95 0.31 1.03 0.72Cyclohexene 82.2 356.05 0.27 -0.02 0.29Cyclopentanone 84.1 403.65 -3.39 -2.69 0.70Thiophene 84.1 357.15 -0.92 -1.20 0.272-Methyl-1-pentene 84.2 335.25 1.05 1.04 0.01Cyclohexane 84.2 353.85 0.79 0.22 0.561-Hexene 84.2 336.55 1.23 1.12 0.114-Methylpent-1-ene 84.2 327.05 1.41 1.10 0.31Methylcyclopentane 84.2 344.95 1.17 0.33 0.84Dichloromethane 84.9 313.15 -0.88 -0.59 0.29Methyl acrylate 86.1 353.35 -2.09 -1.56 0.54Vinyl acetate 86.1 345.65 -1.68 -1.33 0.35Isopropyl methyl ketone 86.1 367.45 -2.40 -1.89 0.513-Pentanone 86.1 375.05 -2.44 -1.92 0.522-Pentanone 86.1 375.35 -2.47 -1.91 0.563-Methyl-1-butanal 86.1 365.65 -1.78 -1.78 0.002,3-Dimethylbutane 86.2 331.05 1.68 0.92 0.762,2-Dimethylbutane 86.2 322.85 1.79 1.37 0.433-Methylpentane 86.2 336.35 1.84 1.01 0.832-Methylpentane 86.2 333.35 1.84 1.06 0.78n-Hexane 86.2 341.85 1.87 1.10 0.77Ethyl acetate 88.1 350.25 -2.26 -1.48 0.78Methyl Propionate 88.1 352.95 -2.15 -1.55 0.60

96

Isopentanol 88.1 404.25 -3.24 -2.50 0.742-Methyl-2-butanol* 88.2 375.55 -3.25 -0.70 2.553-Pentanol 88.2 389.35 -3.09 -2.37 0.73Methyl tert-butyl ether 88.2 328.35 -1.62 -0.75 0.872-Pentanol 88.2 392.45 -3.22 -2.43 0.792,2-Dimethyl-1-propanol 88.2 386.65 -2.66 -1.97 0.691-Pentanol 88.2 411.05 -3.27 -2.48 0.79Ethyl propyl ether 88.2 336.35 -1.33 -0.83 0.50sec-Butyl Methyl Ether 88.2 338.15 -1.22 -1.04 0.18Methyl n-butyl ether 88.2 343.25 -1.14 -0.95 0.19Ethyl carbamate* 89.1 458.15 -5.58 -4.27 1.312-Nitropropane 89.1 393.35 -2.31 -1.93 0.381-Nitropropane 89.1 404.25 -2.45 -2.02 0.43Diethyl sulfide 90.2 365.25 -1.44 -0.03 1.412-Butanethiol 90.2 357.65 -0.53 -0.43 0.10n-Butyl mercaptan 90.2 371.65 -0.43 -0.51 0.08Cycloheptatriene 92.1 390.15 -0.73 -0.33 0.40Toluene 92.1 383.75 -0.58 -0.68 0.11Chloroacetone 92.5 392.15 -3.17 -3.52 0.341-Chloro-2,3-Epoxypropane 92.5 390.15 -2.91 -3.03 0.12Isobutyl Chloride 92.6 341.65 -0.09 0.00 0.101-Chlorobutane 92.6 351.75 -0.17 0.01 0.172-Chlorobutane 92.6 341.15 -0.01 0.01 0.02tert-Butyl chloride 92.6 323.15 -0.28 0.44 0.72Phenol 94.1 454.95 -4.87 -4.30 0.56Dimethyldisulfide 94.2 382.95 -1.31 -1.34 0.03Bromomethane 94.9 311.65 -0.51 -0.64 0.13Furfural 96.1 434.85 -3.86 -2.99 0.87Fluorobenzene 96.1 357.85 -0.59 -0.57 0.024-Methyl-3-penten-2-one 98.1 403.15 -2.82 -2.71 0.11Cyclohexanone 98.2 428.55 -3.43 -2.46 0.973-Methylthiophene 98.2 388.65 -0.53 -1.28 0.75Cycloheptane 98.2 391.55 0.58 0.25 0.331-Heptene 98.2 366.75 1.24 1.09 0.142-Heptene 98.2 371.15 1.23 0.77 0.47trans-2-Heptene 98.2 371.15 1.25 0.77 0.48Methylcyclohexane 98.2 374.05 1.24 0.53 0.721,2-Dichloroethane 99.0 356.65 -1.32 -1.00 0.32

97

1,2-Dichloroethene (Cis) 99.0 328.15 -0.78 -0.51 0.271,1-Dichloroethane 99.0 330.55 -0.64 -0.54 0.101,2-Dichloroethene (trans) 99.0 328.15 -0.42 -0.51 0.09Ethyl acrylate 100.1 372.55 -1.86 -1.39 0.46Methyl methacrylate 100.1 373.65 -1.86 -1.03 0.83Cyclohexanol 100.2 433.95 -3.75 -3.12 0.623,3-Dimethyl-2-butanone 100.2 379.25 -2.05 -1.80 0.254-Methyl-2-pentanone 100.2 389.65 -2.25 -1.85 0.402-Hexanone 100.2 400.75 -2.42 -1.89 0.533-Hexanone 100.2 396.65 -2.29 -1.83 0.46Hexanal 100.2 404.15 -2.06 -1.83 0.233-Methylhexane 100.2 364.15 1.83 1.03 0.802-Methylhexane 100.2 363.15 2.15 1.05 1.103,3-Dimethylpentane 100.2 359.15 1.88 1.25 0.632,4-Dimethylpentane 100.2 353.55 1.89 1.04 0.852,2-Dimethylpentane 100.2 352.35 2.11 1.38 0.73Heptane 100.2 371.65 1.91 1.07 0.852-Methylhexane 100.2 363.15 2.15 1.05 1.10Isopropyl acetate 102.1 361.75 -1.94 -1.36 0.59Ethyl Propionate 102.1 372.25 -1.99 -1.39 0.60N-Propylacetate 102.1 374.65 -2.05 -1.42 0.63Methylbutyrate 102.1 375.95 -2.08 -1.46 0.62Phenylacetylene 102.1 416.15 -1.61 -1.11 0.494-Methyl-2-pentanol 102.2 404.75 -2.74 -2.33 0.412-Hexanol 102.2 409.15 -3.00 -2.26 0.74Ethyl t-butyl ether 102.2 346.25 -1.25 -0.54 0.702,3-Dimethyl-2-butanol 102.2 391.55 -3.39 -0.67 2.723-Methyl-3-pentanol 102.2 395.55 -3.14 -0.58 2.562-Methyl-2-Pentanol 102.2 394.25 -2.84 -0.55 2.28Isopropyl ether 102.2 341.65 -1.03 -0.77 0.261-Hexanol 102.2 430.75 -3.16 -2.38 0.774-Oxaheptane 102.2 363.15 -1.05 -0.80 0.25Benzonitrile 103.1 464.25 -2.67 -2.95 0.284-Cyanopyridine 104.1 486.65 -4.42 -4.07 0.353-Cyanopyridine 104.1 480.05 -4.95 -3.93 1.02Diethoxymethane 104.1 361.15 -2.56 -2.78 0.22Styrene 104.2 418.15 -0.95 -1.12 0.171-Pentanethiol 104.2 399.75 -0.31 -0.53 0.23

98

Isopropyl nitrate 105.1 373.15 -1.18 -0.95 0.23Benzaldehyde 106.1 452.15 -2.96 -2.87 0.09o-Xylene 106.2 411.65 -0.67 -0.73 0.06Ethylbenzene 106.2 409.25 -0.49 -0.68 0.19p-Xylene 106.2 411.45 -0.55 -0.73 0.18m-Xylene 106.2 412.25 -0.53 -0.74 0.212-Chloroethyl vinyl ether 106.6 381.15 -0.45 -1.98 1.532-Chloropentane 106.6 372.15 -0.22 -0.03 0.193-Chloropentane 106.6 370.65 0.03 0.00 0.031-Chloropentane 106.6 380.95 -0.01 -0.02 0.01Benzyl alcohol 108.1 478.45 -4.86 -4.47 0.39m-Hydroxytoluene 108.1 475.35 -4.46 -4.23 0.22p-Hydroxytoluene 108.1 475.05 -4.39 -4.23 0.16Methoxybenzene 108.1 426.85 -1.70 -1.80 0.10Methyl chloroacetate 108.5 402.65 -3.01 -2.88 0.13Thiophenol 110.2 442.25 -1.86 -1.86 0.002,3-Dichloropropene 111.0 367.15 -0.77 -0.36 0.411,5-Dimethylcyclohexane 112.2 396.65 1.16 0.77 0.39Ethylcyclohexane 112.2 405.05 1.09 0.45 0.64cis-1,2-Dimethylcyclohexane 112.2 396.65 1.16 0.77 0.40trans-1,2-Dimethylcyclohexane 112.2 396.65 1.35 0.77 0.581-Octene 112.2 396.15 1.41 1.04 0.37cis-1,4-Dimethylcyclohexane 112.2 392.55 1.55 0.85 0.71trans-1,4-Dimethylcyclohexane 112.2 392.55 1.55 0.85 0.71Propylcyclopentane 112.2 404.15 1.56 0.26 1.30Chlorobenzene 112.6 404.85 -0.90 -1.01 0.121,2-Dichloropropane 113.0 368.65 -0.94 -0.88 0.061,3-Dichloropropane 113.0 394.05 -1.40 -1.18 0.22Ethyl cyanoacetate 113.1 483.15 -4.93 -4.42 0.51Diisopropyl ketone 114.2 398.55 -1.84 -1.61 0.235-Methyl-2-Hexanone 114.2 417.15 -2.23 -1.88 0.352-Heptanone 114.2 424.15 -2.16 -1.85 0.313-Heptanone 114.2 420.15 -2.43 -1.79 0.644-Heptanone 114.2 417.15 -2.65 -1.73 0.92Heptanal 114.2 425.95 -1.96 -1.76 0.193-Methylcyclohexanol 114.2 440.15 -3.82 -2.55 1.272-Methylcyclohexanol 114.2 438.15 -3.51 -2.51 1.002,2,4-Trimethylpentane 114.2 372.35 2.09 1.35 0.75

99

2,2,3-Trimethylpentane 114.2 383.15 1.91 1.14 0.782,3,4-Trimethylpentane 114.2 386.65 1.86 0.77 1.093-Methylheptane 114.2 391.15 2.18 1.03 1.15n-Octane 114.2 398.75 2.12 1.05 1.072,2-Dimethylhexane 114.2 379.95 2.18 1.37 0.802-Nonanol 114.3 466.65 -2.70 -2.05 0.65Bis(chloromethyl)ether 115.0 379.15 -2.07 -2.92 0.85Methyl acetoacetate* 116.1 444.85 -4.95 -4.39 0.56n-Butyl acetate 116.2 399.25 -1.94 -1.38 0.56sec-Butyl acetate 116.2 389.65 -1.73 -1.37 0.36n-Propylpropionate 116.2 395.66 -1.79 -1.33 0.461-Heptanol 116.2 449.55 -3.11 -2.28 0.84Dimethyl oxalate 118.1 436.65 -3.92 -3.94 0.021,1-Diethoxyethane 118.2 375.35 -2.40 -2.71 0.321,2-Diethoxyethane 118.2 392.55 -2.59 -1.36 1.23a-Methylstyrene 118.2 438.55 -0.98 -0.64 0.34p-Methylstyrene 118.2 445.95 -0.89 -1.19 0.31Trichloromethane 119.4 334.25 -0.82 -0.38 0.44Acetophenon 120.2 475.15 -3.37 -3.80 0.43P-Tolualdehyde 120.2 477.65 -3.15 -2.92 0.23Methyl Ethyl Benzene 120.2 435.15 -0.60 -0.71 0.11p-Ethyltoluene 120.2 435.15 -0.69 -0.71 0.021,2,3-Trimethylbenzene 120.2 449.25 -0.75 -0.99 0.25o-Ethyltoluene 120.2 438.35 -0.65 -0.77 0.13Isopropylbenzene 120.2 425.55 -0.33 -0.62 0.291,2,4-Trimethylbenzene 120.2 442.45 -0.60 -0.86 0.26n-Propylbenzene 120.2 432.35 -0.37 -0.64 0.271,3,5-Trimethylbenzene 120.2 437.85 -0.45 -0.76 0.321-Chlorohexane 120.6 408.15 0.00 -0.04 0.04N,N-Dimethylaniline 121.2 466.60 -2.63 -2.33 0.30p-Hydroxybenzaldehyde 122.1 583.15 -7.68 -7.62 0.06m-Hydroxybenzaldehyde 122.1 513.15 -6.99 -5.92 1.07o-Hydroxybenzaldehyde 122.1 470.15 -3.64 -5.09 1.452-Phenylethanol 122.2 491.35 -4.98 -4.23 0.752,4-Dimethylphenol 122.2 484.05 -4.41 -3.90 0.51Ethoxybenzene 122.2 442.95 -1.74 -1.63 0.11p-Ethylphenol 122.2 491.05 -4.50 -4.07 0.433,5-Dimethylphenol 122.2 494.85 -4.60 -4.15 0.45

100

3,4-Dimethylphenol 122.2 500.15 -4.77 -4.28 0.492,5-Dimethylphenol 122.2 484.25 -4.34 -3.91 0.432,3-Dimethylphenol 122.2 490.05 -2.11 -4.10 1.99m-Ethylphenol 122.2 491.55 -4.59 -4.08 0.51Diethyl disulfide 122.2 427.25 -1.06 -0.92 0.14Ethyl Chloroacetate 122.6 417.45 -2.78 -2.67 0.112-Bromopropane 123.0 332.65 -0.35 -0.14 0.211-Bromopropane 123.0 344.15 -0.52 -0.16 0.37Nitrobenzene 123.1 483.95 -3.01 -2.99 0.02o-Methoxyphenol 124.1 478.15 -4.31 -4.72 0.411,4-Dichloro-2-butene(trans) 125.0 425.66 -1.57 -1.63 0.061,4-Dichloro-2-butene(cis) 125.0 425.65 -0.46 -1.63 1.173,4-Dichloro-1-butene 125.0 389.15 -0.46 -1.81 1.351-Nonene 126.2 420.05 1.51 1.06 0.45alpha-Chlorotoluene 126.6 452.15 -1.77 -1.95 0.17o-Chlorotoluene 126.6 432.15 -0.84 -1.06 0.23p-Chlorotoluene 126.6 435.55 -0.75 -1.13 0.38m-Chlorotoluene 126.6 434.95 -0.18 -1.12 0.942,3-Dichlorobutane 127.0 391.15 -0.53 -0.97 0.441,4-Dichlorobutane 127.0 434.15 -1.70 -1.48 0.23Butyl acrylate 128.2 418.15 -1.73 -1.27 0.46Isobutyl acrylate 128.2 405.15 -1.51 -1.18 0.33Naphthalene 128.2 491.05 -1.75 -1.94 0.202-Octanone 128.2 445.65 -2.11 -1.79 0.32Octanal 128.2 444.15 -1.68 -1.64 0.04Nonane 128.3 423.95 2.14 1.05 1.102,2,5-Trimethylhexane 128.3 397.15 2.00 1.38 0.624-Methyloctane 128.3 415.55 2.61 1.05 1.56Chlorobromomethane 129.4 341.15 -1.22 -1.02 0.20Acetoacetic ester 130.1 453.95 -4.31 -4.08 0.23Ethyl valerate 130.2 419.25 -1.82 -1.30 0.52Ethyl Isovalerate 130.2 408.15 -1.54 -1.24 0.29Isoamyl acetate 130.2 415.65 -1.62 -1.37 0.25n-Amyl acetate 130.2 422.35 -1.80 -1.34 0.46N-Propylbutyrate 130.2 416.15 -1.59 -1.23 0.35n-Butyl propionate 130.2 419.95 -1.69 -1.31 0.38Methyl Hexanoate 130.2 422.65 -1.82 -1.34 0.482-Octanol 130.2 453.15 -2.30 -2.19 0.11

101

2-Ethyl-1-Hexanol 130.2 457.75 -2.97 -2.10 0.871-Octanol 130.2 468.25 -3.00 -2.18 0.82Di-n-Butyl ether 130.2 413.35 -0.61 -0.76 0.15Trichloroethene 131.4 360.35 -0.40 -0.27 0.12Trichloroethylene 131.4 360.35 -0.40 0.27 0.672,2,3,3-Tetrafluoro-1-propanol 132.1 382.65 -3.59 -2.28 1.31Ethoxyethylacetate* 132.2 429.55 -3.88 -3.51 0.382,4,6-Trimethyl-1,3,5-trioxane 132.2 397.45 -3.16 -2.26 0.901,2,3,4-Tetrahydronaphthlene 132.2 480.75 -1.26 -1.15 0.101-Heptanethiol 132.3 450.15 0.00 -0.56 0.561,1,2-Trichloroethane 133.4 386.95 -1.47 -1.44 0.031,1,1-Trichloroethane 133.4 347.15 -0.15 0.04 0.19o-Diethylbenzene 134.2 457.15 -0.97 -0.68 0.29m-Cymene 134.2 448.25 -0.53 -0.59 0.06tert-Butylbenzene 134.2 442.25 -0.27 -0.65 0.38p-Diethylbenzene 134.2 454.15 -0.51 -0.62 0.11m-Diethylbenzene 134.2 454.25 -0.47 -0.62 0.15p-Cymene 134.2 449.65 -0.35 -0.62 0.27o-Cymene 134.2 451.25 -0.33 -0.65 0.32sec-Butylbenzene 134.2 449.65 -0.14 -0.61 0.47n-Butylbenzene 134.2 456.45 -0.19 -0.64 0.45Isobutylbenzene 134.2 445.85 0.14 -0.58 0.72Acetanilide 135.2 577.15 -6.64 -6.71 0.07Methyl benzoate 136.2 472.15 -2.88 -2.85 0.032,3,6-Trimethylphenol 136.2 499.15 -3.79 -3.73 0.07p-Propylphenol 136.2 505.75 -4.33 -3.88 0.45d-Limonene 136.2 451.15 0.02 -0.14 0.171-Bromobutane 137.0 374.75 -0.45 -0.20 0.25tert-Butyl bromide 137.0 346.45 0.22 0.27 0.04o-Nitrotoluene 137.1 495.15 -3.29 -2.74 0.553-Nitrotoluene 137.1 505.15 -3.42 -2.96 0.464-Nitrotoluene 137.1 511.45 -3.64 -3.10 0.54Trichlorofluoromethane 137.4 296.85 0.60 0.44 0.162-Phenoxyethanol 138.2 518.15 -5.71 -5.11 0.612-Methoxy-4-methylphenol 138.2 494.15 -4.26 -4.27 0.01Decahydronaphthalene (cyclic) 138.3 460.45 1.28 -1.70 2.993-Ethyl-5-methylphenol 139.2 508.85 -4.56 -3.95 0.61P-MENTHANE (cyclic) 140.3 445.15 1.86 0.66 1.20

102

1-Decene 140.3 443.15 2.04 1.08 0.961,5-Dichloropentane 141.0 452.15 -1.64 -1.35 0.29Iodomethane 141.9 315.65 -0.67 -0.28 0.39n-Butyl methacrylic 142.2 433.15 -1.69 -0.54 1.151-Methylnaphthalene 142.2 513.15 -1.68 -1.93 0.252-Methylnaphthalene 142.2 514.25 -1.67 -1.96 0.282,6-Dimethyl-4-heptanone 142.2 442.55 -2.32 -0.45 1.872-Nonanone 142.2 468.45 -1.82 -1.78 0.045-Nonanone 142.2 460.65 -1.92 -1.64 0.29Nonanal 142.2 464.15 -1.52 -1.57 0.05n-Decane 142.3 447.25 2.32 1.06 1.27o-Chloroanisole 142.6 471.65 -2.43 -2.16 0.271,5-Dichloro-3-oxapentane 143.0 451.65 -3.16 -3.36 0.211-Bromo-2-chloroethane 143.4 380.15 -1.43 -1.21 0.22Dimethyl maleate 144.1 466.15 -4.54 -4.39 0.15Dimethyl fumarate 144.1 466.15 -4.54 -4.39 0.15a-Naphthol 144.2 561.15 -5.63 -5.25 0.38ß-Naphthol 144.2 558.15 -5.95 -5.18 0.77Isobutyl Isobutyrate 144.2 421.75 -1.47 -1.13 0.34Amyl Propionate 144.2 441.75 -1.46 -1.26 0.20Hexyl ethanoate 144.2 444.65 -1.66 -1.30 0.36Butyl butanoate 144.2 440.65 -1.55 -1.24 0.321-Nonanol 144.3 486.45 -2.90 -2.09 0.81Benzotrifluoride 146.1 375.25 -0.17 0.21 0.38Ethyl oxalate 146.1 458.85 -4.04 -3.23 0.81Coumarin 146.2 574.85 -4.99 -5.39 0.40Butyl lactate 146.2 459.15 -4.11 -4.18 0.07t-Butyl peroxide 146.2 384.15 0.30 0.29 0.012-Ethyl-1,3-Hexandiol 146.2 517.15 -6.25 -5.26 0.991,2-Dichlorobenzene 147.0 453.15 -1.11 -1.41 0.311,3-Dichlorobenzene 147.0 446.15 -0.97 -1.27 0.301,4-Dichlorobenzene 147.0 447.15 -1.01 -1.29 0.281,2,3-Trichloropropane 147.4 430.15 -1.85 -1.97 0.12Phthalic anhydride 148.1 568.15 -6.18 -6.37 0.20Pentamethylbenzene 148.3 505.15 -1.75 -1.20 0.55Pentyl benzene 148.3 478.55 0.02 -0.61 0.631-Chloroocatne 148.7 454.65 0.19 0.00 0.201,2,3,5-Tetrafluorobenzene 150.1 357.55 -0.10 -0.17 0.08

103

1,2,4,5-Tetrafluorobenzene 150.1 363.35 -0.14 -0.28 0.14Benzyl acetate 150.2 486.15 -3.34 -3.18 0.15Phenyl glycidyl ether 150.2 516.15 -4.47 -4.52 0.04Ethyl benzoate 150.2 485.15 -2.52 -2.63 0.11Thymol 150.2 505.65 -4.70 -3.47 1.241-Bromo-3-methylbutane 151.0 393.55 0.15 -0.22 0.371-Bromopentane 151.1 402.95 -0.09 -0.23 0.13Methyl salicylate 152.1 496.06 -2.40 -4.89 2.49Acenaphthylene 152.2 553.15 -2.29 -2.97 0.682-Nitroanisole 153.1 550.15 -4.76 -4.25 0.51Carbon tetrachloride 153.8 349.95 0.05 0.28 0.222,6-Dimethoxyphenol 154.2 534.15 -5.02 -5.49 0.46Biphenyl 154.2 529.25 -1.90 -2.07 0.17Acenaphthene 154.2 552.15 -2.13 -2.75 0.62alpha-Terpineol (cylic) 154.3 490.65 -3.30 -2.77 0.54Iodoethane 156.0 345.65 -0.55 -0.26 0.291-Ethylnaphthalene 156.2 531.75 -1.55 -1.86 0.312-Ethylnaphthalene 156.2 531.15 -1.66 -1.85 0.191,8-Dimethylnaphthalene 156.2 538.15 -1.84 -1.99 0.151,5-Dimethylnaphthalene 156.2 538.15 -1.84 -1.99 0.152,3-Dimethylnaphthalene 156.2 541.15 -1.42 -2.06 0.64Decanal 156.3 481.65 -1.13 -1.46 0.33n-Undecane 156.3 469.05 1.90 1.08 0.82Bromobenzene 157.0 429.15 -1.00 -1.13 0.141,2-Chloronitrobenzene 157.6 518.65 -3.42 -3.18 0.241,3-Nitrochlorobenzene 157.6 508.65 -3.26 -2.96 0.301,4-Nitrochlorobenzene 157.6 515.15 -3.70 -3.10 0.60Ethyl Heptanoate 158.2 460.15 -1.69 -1.15 0.54Methyl octanoate 158.2 466.05 -1.49 -1.28 0.211-Decanol 158.3 504.25 -2.88 -2.00 0.88Diethyl Malonate 160.2 473.15 -4.07 -3.55 0.52(Dichloromethyl)benzene 161.0 478.15 -1.79 -2.33 0.543,4-Dichlorotoluene 161.0 482.05 -0.98 -1.53 0.55Hexylbenzene 162.3 499.25 0.07 -0.57 0.64Hexamethylbenzene 162.3 536.55 -1.50 -1.40 0.101-Chloronaphthalene 162.6 532.15 -1.84 -2.27 0.442-Chloronaphthalene 162.6 529.15 -1.88 -2.21 0.32Bromodichloromethane 163.8 363.15 -1.06 -1.30 0.23

104

Trichloronitromethane 164.4 385.15 -1.08 -1.88 0.80Methoxyflurane 165.0 378.15 -0.82 -2.07 1.251-Bromohexane 165.1 428.45 0.13 -0.24 0.36Tetrachloroethene 165.8 394.45 -0.14 0.32 0.46Fluorene 166.2 568.15 -2.41 -2.83 0.431,1,2,2-Tetrachloroethane 167.9 419.65 -1.82 -1.96 0.141,1,1,2-Tetrachloroethane 167.9 403.65 -1.00 -0.90 0.111,1,1,3,3,3-Hexafluoro-2-propanol 168.0 332.15 -2.76 -0.06 2.701,3-Dinitrobenzene 168.1 564.15 -5.70 -4.57 1.13Dibenzofuran 168.2 560.15 -2.06 -2.82 0.76Diphenylmethane 168.2 538.15 -2.28 -2.09 0.192-Iodopropane 170.0 362.65 -0.55 -0.23 0.321-Iodopropane 170.0 375.75 -0.43 -0.29 0.14o-Hydroxybiphenyl 170.2 559.15 -4.37 -4.44 0.07Diphenyl ether 170.2 531.15 -1.94 -2.44 0.506-Undecanone 170.3 500.15 -2.04 -1.52 0.522-Undecanone 170.3 504.65 -2.59 -1.60 0.98Dodecane 170.3 489.45 2.53 1.12 1.41p-Bromotoluene 171.0 457.45 -1.02 -1.22 0.20m-Bromotoluene 171.0 456.85 -0.56 -1.21 0.652,6-Dichlorobenzonitrile 172.0 543.15 -3.38 -3.53 0.151-Nitronaphthalene 173.2 577.15 -4.14 -3.66 0.48Diethyl succinate 174.2 490.85 -4.67 -3.76 0.911-Phenylheptane 176.3 513.15 -0.21 -0.40 0.19Methyleugenol 178.2 543.65 -3.64 -2.42 1.22Butyl benzoate 178.2 523.45 -2.79 -1.98 0.81phenanthrene 178.2 613.15 -2.76 -3.29 0.53Anthracene 178.2 613.05 -2.64 -3.29 0.641-Bromoheptane 179.1 452.15 0.27 -0.23 0.507,8-Benzoquinoline 179.2 612.15 -5.15 -3.92 1.231,2,3-Trichlorobenzene 181.5 491.65 -1.29 -1.66 0.371,3,5-Trichlorobenzene 181.5 481.15 -1.11 -1.44 0.332,4-Dinitrotoluene 182.1 573.15 -5.66 -4.28 1.372,6-Dinitrotoluene 182.1 573.15 -4.52 -4.28 0.23trans-Azobenzene 182.2 566.15 -3.26 -2.70 0.562-Iodobutane 184.0 393.15 -0.09 -0.29 0.19N-Butyl Iodide 184.0 403.75 -0.17 -0.32 0.15Diphenylcarbinol 184.2 571.15 -6.27 -5.18 1.09

105

Dibenzothiophene 184.3 605.65 -2.86 -3.62 0.76n-Tridecane 184.4 508.55 2.07 1.14 0.93Isoflurane 184.5 321.65 0.07 -0.45 0.52(2-Bromoethyl)benzene 185.1 492.15 -1.21 -2.08 0.87Methyl decanoate 186.3 497.15 -1.07 -0.97 0.11Dodecanol 186.3 532.15 -3.04 -1.66 1.381,8-Dichloro-3,6-dioxaoctane 187.1 505.15 -4.50 -5.08 0.581,1,2-Trifluoro-1,2,2-trichloroethane 187.4 320.85 1.33 1.53 0.191,2-Dibromoethane 187.9 404.75 -1.56 -1.46 0.102-Chlorobiphenyl 188.7 563.15 -1.52 -2.27 0.753-Chlorobiphenyl 188.7 557.65 -1.60 -2.15 0.544-Chlorobiphenyl 188.7 566.05 -1.63 -2.34 0.70n-Octylbenzene 190.3 537.65 0.24 -0.49 0.731,4-Bromochlorobenzene 191.5 469.15 -1.23 -1.39 0.161,4-Dichloro-4-nitrobenzene 192.0 528.65 -3.48 -2.84 0.641,4-Dichloro-2-Nitrobenzene 192.0 540.15 -3.31 -3.09 0.221-Bromooctane 193.1 473.15 0.38 -0.19 0.56Dimethyl phthalate 194.2 556.85 -5.37 -4.66 0.711,4-Dicarbomethoxybenzene 194.2 561.15 -2.26 -4.75 2.492,4,5-Trichlorotoluene 195.5 504.15 -1.21 -1.44 0.232-Bromo-2-chloro-1,1,1-trifluoroethane 197.4 323.35 -0.08 0.84 0.921-Iodopentane 198.1 428.15 -0.10 -0.30 0.20Dibenzyl ether 198.3 571.15 -3.56 -4.22 0.66Tetradecane 198.4 526.65 2.58 1.20 1.371-Naphthyl methylcarbamate 201.2 588.15 -6.75 -5.06 1.681,3-Dibromopropane 201.9 440.45 -1.44 -1.67 0.231,2-Dibromopropane 201.9 415.05 -1.22 -1.33 0.11m-Nitrobromobenzene 202.0 529.15 -4.12 -3.06 1.06Fluoranthene 202.3 657.15 -3.44 -4.08 0.64Pyrene 202.3 677.15 -3.31 -4.55 1.24Pentachloroethane 202.3 432.95 -1.10 -1.37 0.27Pebulate 203.4 475.15 -2.01 -1.15 0.861,1,2,2-Tetrachlorodifluoroethane 203.8 366.15 0.66 0.76 0.101,1,1,2-Tetrachloro-2,2-difluoroethane 203.8 364.65 0.78 0.15 0.63Iodobenzene 204.0 461.55 -1.29 -1.50 0.21

106

1-Bromonaphthalene 207.1 554.15 -1.93 -2.41 0.48Anthraquinone 208.2 650.15 -6.02 -4.45 1.56Dibromochloromethane 208.3 393.15 -1.49 -1.63 0.142,3,6-Trichloroanisole 211.5 500.15 -1.93 -1.65 0.28Iodohexane 212.1 454.15 0.06 -0.34 0.40n-Pentadecane 212.4 543.75 2.71 1.27 1.44Desmetryn 213.3 618.15 -7.70 -6.27 1.431-Tetradecanol 214.4 562.15 -2.18 -1.45 0.731,2,3,4-Tetrachlorobenzene 215.9 527.15 -1.51 -1.87 0.361,2,4,5-Tetrachlorobenzene 215.9 517.65 -1.39 -1.66 0.27Diethyl pimelate 216.3 527.15 -4.74 -3.13 1.611,2-Benzofluorene 216.3 678.15 -2.96 -4.02 1.05Glyceryl triacetate 218.2 532.15 -6.30 -5.75 0.551-Phenyldecane 218.4 571.15 0.80 -0.30 1.10p-Nonylphenol 220.4 566.15 -2.86 -2.28 0.57Diethyl phthalate 222.2 568.15 -4.60 -3.96 0.653,3'-Dichlorobiphenyl 223.1 593.15 -2.02 -2.39 0.374,4'-Dichlorobiphenyl 223.1 590.15 -2.09 -2.33 0.24Iodoheptane 226.1 477.15 0.20 -0.34 0.54Hexadecane 226.5 559.95 1.29 1.36 0.07Trinitroglycerine 227.1 523.15 -5.39 -3.70 1.70Ametryn 227.3 618.15 -7.01 -5.76 1.25Dibutyl Maleate 228.3 554.15 -4.82 -3.45 1.36Triphenylene 228.3 698.15 -5.20 -3.92 1.281,2-Benzanthracene 228.3 710.75 -3.31 -4.23 0.923,4-Benzophenanthrene 228.3 721.15 -3.67 -4.48 0.81Chrysene 228.3 721.15 -3.67 -4.48 0.81m-Terphenyl 230.3 636.15 -3.84 -2.43 1.41o-Terphenyl 230.3 605.15 -2.60 -1.73 0.871,3-Dibromobenzene 235.9 491.15 -1.30 -1.50 0.211,4-Dibromobenzene 235.9 493.15 -1.44 -1.55 0.111,2-Dibromo-3-chloroprpane 236.3 469.15 -2.22 -2.56 0.341-Hexadecanol 242.5 607.15 -2.53 -1.65 0.88Perchloropropylene 248.8 482.65 -0.72 -0.68 0.04Pentachlorobenzene 250.3 550.15 -1.54 -1.82 0.28Benzo(k)fluoranthene 252.3 753.15 -4.62 -5.02 0.40Tribromomethane 252.7 422.25 -1.66 -1.35 0.31Hexachlorobutadiene 260.8 488.15 -0.38 0.25 0.63

107

Pentachlorotoluene 264.4 574.15 -1.50 -1.88 0.382,4,5,6-Tetrachloro-1,3-benzenedicarbonitile 265.9 623.15 -4.09 -4.43 0.34Diiodomethane 267.8 455.15 -1.88 -1.93 0.05Indeno(1,2,3-CD)pyrene 276.3 809.15 -4.85 -6.17 1.32Dibutyl phthalate 278.4 613.15 -4.13 -3.14 0.99N-(1-ethylpropyl)-2,6-dinitro-3,4-xylidine 281.3 603.15 -4.46 -2.26 2.19Hexachlorobenzene 284.8 598.15 -1.16 -2.35 1.201a,2a,3ß,4a,5a,6ß-hexachlorocyclohexane 290.8 561.15 -3.68 -2.46 1.21Pentachloronitrobenzene 295.3 601.15 -2.74 -2.80 0.06Butyl benzyl phthalate 312.4 643.15 -4.29 -3.85 0.44Dibutyl sebacate 314.5 617.65 -5.70 -2.03 3.681,3,5-Tribromobenzene 314.8 544.15 -1.49 -1.75 0.251,1-Dichloro-2,2-bis(4-chlorophenyl)ethylene 318.0 609.15 -2.77 -1.67 1.10Carbon tetrabromide 331.6 462.65 -1.70 -1.03 0.67Dacthal 332.0 638.15 -4.05 -4.33 0.28Benfluralin 335.3 643.15 -1.92 -2.84 0.921,1,2,2-Tetrabromoethane 345.7 517.15 -3.24 -3.15 0.101,1'-(2,2,2-trichloroethylidene-bis(4-methoxy)benzene 345.7 619.15 -5.08 -2.41 2.672-Chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene 361.7 631.35 -4.47 -2.25 2.23DI-2-Ethylhexyl adipate 370.6 690.15 -4.75 -2.39 2.37Bis(2-Ethylhexyl)phthalate 390.6 657.15 -4.96 -0.80 4.15

* Compounds with aqueous solubilities greater than 1.0 mol/l.

108

APPENDIX E: RESULTS OF THE AIR-WATER PARTITION COEFFICIENT

ESTIMATIONS FOR IONIZABLE COMPOUNDS AND THOSE WITH

AQUEOUS SOLUBILITIES OF GREATER THAN 50%

Table D.1 Chemical Name, Molecular Weight, Boiling Point (Kelvin), Experimental and

Predicted log Air-Water Partition Coefficient, and Absolute Error in Prediction for

Ionizable Compounds and those with Aqueous Solubilities of Greater than 50%.

Exper PredName MW Tb (K) log Kaw log Kaw AEMethanol 32.0 337.75 -3.73 -3.15 0.58Acetonitile 41.1 332.75 -2.85 -1.88 0.97Ethanol 46.1 351.35 -3.69 -2.85 0.84Acetone 58.1 328.65 -2.79 -2.09 0.70Allyl alcohol 58.1 370.15 -3.69 -1.94 1.75Propylene oxide 58.1 308.15 -2.55 -1.71 0.83Acetamide 59.1 495.15 -6.74 -6.86 0.121-Aminopropane 59.1 320.35 -3.22 -1.04 2.182-Aminopropane 59.1 304.85 -2.73 -0.95 1.78Ethanoic acid 60.1 391.05 -5.39 -4.41 0.981-Propanol 60.1 370.35 -3.52 -2.70 0.822-Propanol 60.1 355.45 -3.48 -2.74 0.74Diaminoethane 60.1 390.15 -7.15 -3.86 3.291,2-Ethanediol 62.1 468.15 -5.61 -7.26 1.652-Fluoroethanol 64.1 376.65 -4.13 -3.24 0.90Acrylamide 71.1 465.75 -7.39 -5.05 2.34Pyrrolidine 71.1 359.65 -4.01 -3.08 0.93Acrylic acid 72.1 414.35 -4.82 -4.42 0.40Tetrahydrofuran 72.1 338.15 -2.54 -1.44 1.10n-Methylacetamide 73.1 478.15 -5.76 -5.67 0.09N,N-dimethylformamide 73.1 426.15 -5.52 -2.52 3.00n-Butylamine 73.1 350.15 -3.15 -1.06 2.09tert-Butyl amine 73.1 317.15 -2.83 -0.52 2.31Diethylamine 73.1 328.65 -2.98 -3.90 0.92Isobutylamine 73.1 340.85 -3.26 -1.07 2.19sec-Butylamine 73.1 336.15 -2.20 -0.98 1.221,3-Dioxolane 74.1 351.15 -3.00 -2.89 0.11propionic acid 74.1 414.25 -4.74 -4.37 0.37tert-Butyl alcohol 74.1 355.55 -3.43 -0.81 2.62

109

2-Methoxyethanol 76.1 397.25 -4.87 -4.74 0.13Dimethyl sulfoxide 78.1 462.15 -7.21 -3.48 3.73Pyridine 79.1 388.35 -3.35 -1.91 1.442-Chloroethanol 80.5 401.75 -4.51 -3.71 0.79Piperidine 85.2 379.35 -3.74 -2.73 1.01a-Methylacrylic acid 86.1 436.15 -4.80 -3.96 0.84cis-Crotonic acid 86.1 458.15 -4.76 -5.11 0.352-Methyl-3-butene-2-ol 86.1 370.15 -3.07 -1.56 1.51n-Pentylamine 87.2 377.45 -3.00 -1.07 1.941,4-Dioxane 88.1 374.65 -3.71 -2.60 1.11Butanoic acid 88.1 436.85 -4.66 -4.32 0.34Isobutyric acid 88.1 427.55 -4.44 -4.23 0.211-Methoxy-2-Propanol 90.1 392.15 -4.42 -4.44 0.022-Ethoxyethanol 90.1 408.15 -4.72 -4.43 0.294-Methylpyridine 93.1 418.45 -3.61 -2.00 1.612-Methylpyridine 93.1 402.45 -3.39 -1.69 1.703-Methylpyridine 93.1 417.25 -3.50 -1.98 1.52Aniline 93.1 457.25 -4.08 -3.57 0.522-Methylpyrazine 94.1 410.15 -4.05 -2.49 1.56a-Chloroacetic acid 94.5 462.45 -6.41 -5.80 0.62Furfuryl alcohol 98.1 444.15 -5.49 -4.46 1.04Cyclohexanamine 99.2 407.15 -3.77 -1.63 2.142,2,2-Trifluoroethanol 100.0 347.15 -3.15 -1.57 1.58Diisopropylamine 101.2 357.05 -2.41 -3.75 1.34Dipropylamine 101.2 382.45 -2.68 -3.88 1.20Triethylamine 101.2 362.15 -2.22 1.66 3.88Hexylamine 101.2 405.95 -2.96 -1.12 1.842,2-Dimethylpropanoic acid(pivalic acid) 102.1 437.15 -3.94 -4.09 0.14Pentanoic acid 102.1 459.25 -4.71 -4.29 0.42Isovaleric acid 102.1 449.65 -4.47 -4.23 0.234-Ethylpyridine 107.2 441.45 -3.46 -1.97 1.493-Ethylpyridine 107.2 438.15 -3.37 -1.91 1.472-Ethylpyridine 107.2 421.75 -3.17 -1.58 1.59n-Methylaniline 107.2 469.35 -3.44 -2.66 0.78p-Toluidine 107.2 473.55 -4.08 -3.41 0.67m-Toluidine 107.2 476.45 -4.17 -3.48 0.69o-Toluidine 107.2 473.45 -4.09 -3.41 0.682,4-Dimethylpyridine 107.2 431.65 -3.56 -1.78 1.782,6-Dimethylpyridine 107.2 417.25 -3.37 -1.49 1.882,5-Dimethylpyridine 107.2 430.15 -3.45 -1.75 1.702,3-Dimethylpyridine 107.2 434.35 -3.53 -1.83 1.703,5-Dimethylpyridine 107.2 445.15 -3.55 -2.05 1.503,4-Dimethylpyridine 107.2 452.25 -3.82 -2.19 1.63

110

o-Hydroxytoluene 108.1 464.15 -4.31 -3.97 0.34Phenylhydrazine 108.1 516.65 -6.74 -4.90 1.85m-Phenylenediamine 108.1 558.15 -8.41 -6.70 1.71o-Phenylenediamine 108.1 530.15 -6.53 -5.81 0.72p-Aminophenol 109.1 557.15 -7.41 -7.69 0.281,4-Dihydroxybenzene 110.1 560.15 -8.71 -8.32 0.401,2-Dihydroxybenzene 110.1 518.15 -6.89 -7.61 0.72p-Fluorophenol 112.1 458.65 -4.54 -4.19 0.35o-Fluorophenol 112.1 424.65 -3.88 -3.43 0.452-Chloropyridine 113.5 443.15 -3.18 -2.42 0.76Trifluoroacetic acid 114.0 346.15 -5.34 -2.58 2.76Hexanoic acid 116.2 478.35 -4.51 -4.20 0.312-Ethylbutyric acid 116.2 467.15 -4.18 -4.05 0.142-Butoxyethanol 118.2 441.55 -4.18 -4.11 0.084-Acetylpridine 121.1 485.15 -5.59 -4.67 0.923-Acetylpridine 121.1 493.15 -6.06 -4.84 1.22Benzamide 121.1 563.15 -8.00 -6.12 1.882,6-Dimethylaniline 121.2 488.15 -3.99 -3.23 0.763,4-Xylidine 121.2 501.15 -4.12 -3.52 0.602,5-Dimethylaniline 121.2 487.15 -3.76 -3.21 0.552,4,6-Trimethylpyridine 121.2 443.75 -3.44 -1.53 1.91N-Ethylaniline 121.2 476.15 -3.40 -2.30 1.105-Ethyl-2-Methylpyridine 121.2 451.45 -3.11 -1.69 1.42Benzoic acid 122.1 522.35 -5.81 -5.70 0.112,6-Dimethylphenol 122.2 474.15 -3.57 -3.67 0.11o-Ethylphenol 122.2 477.65 -3.72 -3.64 0.08p-Methoxyaniline 123.2 516.15 -5.57 -4.63 0.94p-Chloroaniline 127.6 505.15 -4.32 -4.01 0.31m-Chloroaniline 127.6 503.65 -4.27 -3.98 0.29o-Chloroaniline 127.6 481.95 -3.66 -3.68 0.024-Chlorophenol 128.6 493.15 -4.59 -4.51 0.083-Chlorophenol 128.6 487.15 -4.85 -4.37 0.482-Chlorophenol 128.6 448.05 -3.34 -3.66 0.32Dichloroacetic acid 128.9 467.15 -4.84 -5.62 0.781,3-Dichloro-2-propanol 129.0 449.15 -4.28 -4.40 0.13Quinoline 129.2 510.25 -4.17 -3.01 1.16Diisobutylamine 129.2 412.75 -1.64 -3.82 2.18Dibutylamine 129.2 432.75 -2.44 -3.90 1.462-Ethylhexylamine 129.2 442.15 -2.41 -1.03 1.38Heptanoic acid 130.2 495.35 -4.86 -4.07 0.792,4,5-Trimethylaniline 135.2 507.65 -3.99 -3.16 0.83Phenylacetic acid 136.2 538.65 -5.78 -5.74 0.032,4,6-Trimethylphenol 136.2 493.15 -3.97 -3.59 0.393-Nitroaniline 138.1 579.15 -6.49 -6.07 0.42

111

4-Nitroaniline 138.1 605.15 -7.29 -6.68 0.612-Nitroaniline 138.1 557.15 -5.62 -5.44 0.18o-Nitrophenol 139.1 489.15 -3.28 -4.65 1.37p-Nitrophenol 139.1 552.15 -7.77 -6.25 1.523-Methyl-4-chlorophenol 142.6 508.15 -4.00 -4.33 0.332-Methyl-4-chlorophenol 142.6 496.15 -4.34 -4.05 0.282-Naphthylamine 143.2 573.15 -5.48 -4.72 0.761-Naphthylamine 143.2 573.95 -5.34 -4.74 0.60Tripropylamine 143.3 429.15 -1.81 1.87 3.68Octanoic acid 144.2 512.15 -4.44 -3.95 0.49Diisopropylethanolamine 145.2 463.15 -4.28 -1.43 2.86Adipic acid 146.1 610.65 -9.72 -9.81 0.10Trichloroacetaldehyde 147.4 370.95 -6.92 -2.43 4.49Cinnamic acid 148.2 573.15 -6.16 -6.87 0.712,6-Diethylaniline 149.2 508.65 -4.34 -2.71 1.634-tert-Butylphenol 150.2 510.15 -4.31 -3.74 0.57o-t-Butylphenol 150.2 496.15 -2.98 -3.31 0.33Vanillin 152.2 558.15 -7.06 -6.72 0.342-Chlorobenzoic acid 156.6 560.15 -5.58 -5.82 0.25Nonanoic acid 158.2 527.65 -4.33 -3.80 0.523,4-Dichloroaniline 162.0 545.15 -3.22 -4.32 1.103,5-Dichlorophenol 163.0 506.15 -5.00 -4.17 0.832,4-Dichlorophenol 163.0 483.15 -4.05 -3.82 0.232,6-Dichlorophenol 163.0 493.15 -3.96 -4.22 0.26Trichloroacetic acid 163.4 469.65 -6.26 -5.08 1.18Diphenylamine 169.2 575.15 -3.86 -4.35 0.49Decanoic acid 172.3 541.85 -4.26 -3.64 0.624-Bromophenol 173.0 511.15 -5.21 -4.47 0.74Phenanthridine 179.2 622.15 -6.17 -4.15 2.035-Methyl-1,2,4-triazolo[3,4-b]benzothiazole 189.2 548.15 -8.90 -3.86 5.032,4,5-Trichlorophenol 197.5 520.15 -4.18 -4.05 0.132,4,6-Trichlorophenol 197.5 519.15 -3.97 -3.85 0.122-Methyl-4,6-dinitrophenol 198.1 651.15 -4.24 -7.74 3.50(4-chloro-o-tolyloxy)acetic acid 200.6 559.89 -7.26 -5.68 1.593-Amino-2,5-dichlorobenzoic acid 206.0 585.15 -8.80 -6.86 1.942-(4-chloro-2-methylphenoxy)propanoic acid 214.7 571.15 -7.40 -5.55 1.85Tetradecanoic acid 228.4 599.35 -4.69 -3.12 1.572-sec-butyl-4,6-Dinitrophenol 240.2 605.15 -4.73 -5.10 0.37Hexadecanoic acid 256.4 624.65 -3.09 -2.81 0.27Pentachlorophenol 266.3 582.65 -6.00 -4.50 1.50Octadecanoic acid 284.5 656.15 -4.71 -2.71 2.00

112

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