NASA TECHNICAL NOTE

40 Qo N N I

n z c 4 m 4 z

CRYOGENIC SOLUTIONS AND SOLUBILITIES IN LIQUID FLUORINE

by Robert E. Seauer

Lewis Research Center Cleueland, Ohio

I

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 0 WASHINGTON, D. C. '" 0, JUNE 1964

https://ntrs.nasa.gov/search.jsp?R=19640013319 2020-03-24T06:24:07+00:00Z

CRYOGENIC SOLUTIONS AND SOLUBILITIES

IN LIQUID FLUORINE

By Robert E. Seaver

Lewis Research Center Cleveland, Ohio

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

For sale by the Office of Technical Services, Department of Commerce, Washington, D.C. 20230 -- Price $0.50

CRYOGENIC SOLUTIONS AND SOLUBILITIES

I N LIQUID FLUORINE

by Robert E. Seaver

Lewis Research Center

SUMMARY

The solubilities of several substances in liquid fluorine have been deter- These experimental mined between 68' and 83' K by vapor-pressure measurements.

data, as well as a summary of literature data on solutions of solids in cryo- genic liquids, are presented and compared with solubilities calculated by as- suming regular solutions. Experimental and calculated values for the solubili- ties of carbon tetrafluoride, perfluorethane, and perchloryl fluoride in liquid fluorine show close agreement, while the solubilities of krypton and xenon in fluorine show considerable deviation from calculated values. Little of the literature data agrees with the calculated solubilities. Deviations from cal- culated values are discussed.

INTRODUCTION

Only a limited amount of past work has been concerned with the prediction of the solubilities of solids in cryogenic liquids. Information on solutions in liquid fluorine is essentially nonexistent, and in the case of carbon tetra- fluoride the solubility data that are available (ref. 1) appear to be in con- siderable error. This lack of information, together with the importance of cryogenic liquids in space applications and the possible use of fluorine as a rocket propellant, prompted the present investigation. It was the intent of this investigation to determine the solubilities of several substances in liquid fluorine and to consider the pxsibility of predicting solubilities in cryogenic liquids in general.

Solubilities of the following substances in liquid fluorine were deter- mined: carbon tetrafluoride (CFq), perfluorethane (CZF~), krypton (=), xenon (Xe), perchloryl fluoride (ClO3F), nitryl fluoride (NOzF), silicon tetrafluo- ride (SiF ), boron trifluoride (EFs), tetrafluoroethylene polymer, cobalt tri- fluoride tCoF3) , and aluminum trifluoride (AlF3). for their physical and chemical properties. In addition, the liquid-liquid systems nitrogen-fluorine (Nz-Fz) and nitrogen trifluoride - fluorine (NF3-F2) were investigated. All solutions were studied in the temperature range 68O to 83' K by vapor-pressure measurements.

Tiiese substances were chosen

data ties from

b

*CP

E

AH

N

P

P

AP

R

T

v

X

6

cp

Experimental solubilities obtained in this study, as well as literature on solutions of solids in cryogenic liquids, are compared with solubili- calculated by assuming regular solutions (refs. 2 and 3). Deviations the calculated values are discussed.

.

SYMBOLS

van derWaal's constant

change in heat capacity

energy of vaporization

heat

number of moles

pres sure

vapor pressure of liquid

vapor-pressure lowering

gas constant

temperature

molar volume

solubility

solubility parameter

volume fraction

Subscripts:

B boiling

C cri t i cal

f melting or fusion

i ideal

j component, solvent or solute

t transition

v vaporization

2

1 solvent

2 solute

EXPERIMENTAL PROCEDURE

All solute materials were obtained commercially except NOzF, which was prepared by reacting fluorine with nitrogen dioxide (ref. 4). The gaseous so l - utes with purities less than 99.9 percent were further purified by bulb-to-bulb distillation, while the solid solutes were used as obtained. Purity of these gases was checked by means of mass spectrometer and infrared analyses. Fluo- rine of 98.0-percent purity was obtained from a low-pressure cylinder and was further purified by bulb-to-bulb distillation at pressures not exceeding 1/2 atmosphere. Analysis of the fluorine was by reaction with cold mercury (ref. 5) and by use of fnfrared spectra. Vapor-pressure measurements of the purified fluorine (at least 99.9-percent purity) agreed with previously re- ported data (ref. 6).

The gases were all handled in a glass vacuum system that had been condi- tioned with fluorine at 1-atmosphere pressure for at least 20 hours. fluorocarbon grease was used on all stopcocks. A soda lime scrubber was used for disposal of the fluorine.

A chloro-

coil

J

/-

(a) Cryostat. (b) Vapor-pressure measurement system.

Figure I. - Eqerimental apparatus.

3

The cryostat and t h e vapor-pressure measurement system a r e shown i n f ig- u re 1. The cryostat consisted of two concentric g l a s s Dewars, each containing l i q u i d nitrogen. The l i q u i d nitrogen i n t h e inner Dewar w a s cooled constantly by cold helium gas flowing through t h e copper cooling c o i l and w a s maintained a t a constant temperature by means of t h e heat ing uni t - The helium gas w a s cooled below 80' K by being passed through l i q u i d helium. The temperature i n the inner Dewar w a s control led t o I tO.03O K and w a s measured by means of a p l a t - inum res i s tance thermometer. s t irred by an e l e c t r i c stirrer,

The l i q u i d nitrogen i n t h e inner Dewar w a s

Two sample bulbs, one f o r pure f luo r ine and one f o r t h e f luo r ine solu- t i ons , were immersed i n t h e inner Dewar. The bulbs were both connected t o a d i f f e r e n t i a l manometer containing chlorofluorocarbon o i l . One bulb w a s con- nected t o another d i f f e r e n t i a l manometer, which w a s i n t u r n connected t o a m e r - cury manometer used f o r absolute-pressure measurements. were taken with t h e a i d of a cathetometer. Samples i n t h e bulbs were s t i r r e d by g l a s s s t i r r i n g rods having tops i n which pieces of s t e e l w e r e enclosed. The s t i r r i n g rods were in t e rmi t t en t ly actuated by an electromagnet. Volumes of t h e sample bulbs and t h e manometers were ca l ibra ted f o r various pressure d i f f e r - en t i a l s ,

All pressure readings

Mixtures of known composition were prepared i n one of t h e sample bulbs by adding a known amount of so lu t e and then condensing a known amount of f luo r ine i n t o t h e bulb. The number of moles of so lu tes t h a t were gases a t room tempera- t u r e w a s determined i n ca l ibra ted bulbs by assuming t h e so lu tes t o be i d e a l gases a t - low pressures (less than 1 a t m ) ; t h e gaseous so lu tes were subsequently condensed o r frozen i n t o t h e sample bulb. The s o l i d so lu tes were weighed be- fo re they were introduced i n t o the sample bulb, Fluorine as a l i q u i d w a s meas- ured out t o 50.002 m i l l i l i t e r i n a ca l ibra ted g lass tube immersed i n l i q u i d ni- trogen, and t h e number of moles w a s determined by applying t h e densi ty da t a of Jarry and Miller ( re f . 7) . by lowering t h e temperature of t h e c ryos ta t below tha t of t h e ca l ibra ted tube.

The f luo r ine w a s t ransfer red i n t o t h e sample bulb

All t h e so lu tes appeared t o be i n e r t t o f luo r ine under t h e conditions of t h i s study, P r io r t o t h i s inves t iga t ion it w a s suspected t h a t t e t r a f luo r -

ethylene polymer might break down while being s t i r r e d with f luo r ine j however, no evidence of decomposition o r reac- t i o n w a s found.

320 -

Solute I" E -0- Carbon tetrafluoride E

Three methods were used t o obtain 240- -0- Krypton

s o l u b i l i t y data, Method 1 consisted i n Q p lo t t i ng vapor-pressure lowering Ap against composition a t a constant t e m - !i5 160-

- B E perature. The'point at which Ap be- VI VI came constant determined t h e s o l u b i l i t y b 80- of t h e solute. This method i s i l l u s - !i t r a t e d i n f igu re 2 f o r the vapor-

pressure lowering of solut ions of CF4 0 .2 . 4 . 6 .8 1 and krypton i n l i q u i d f luo r ine a t

77.5O X. The dF4 so lu t ion w a s nearly idea l , while t he krypton so lu t ion showed a deviation from idea l i ty ,

ideal solution Ci

m c .-

3

m

>

Solubility, x2, mole fraction of solute

Figure 2. - Vapor-pressure lowering of solutions of carbon tetrafluoride and krypton in f luorine at 77.5' K.

4

In method 2 the vapor pressure of the solution was plotted against the temperature for known compositions. curve of an unsaturated solution with that of the saturated solution determined

The intersection of a vapor-pressure

/ ------- Fluorine /' - Saturated solution of krypton

-*- 18.3 Percent krypton -*- 26.4 Percent krypton - Saturated solution of carbon

tetrafluoride -*- 70.2 Percent carbon tetra-

fluoride -+- 83.5 Percent carbon tetra-

fluoride -+- 88.5 Percent carbon tetra-

fluoride

I 89

I 85

I 81

I 77

Temperature, OK

I 73

I 69

20 I 65

Figure 3. - Vapor pressures of solutions of carbon tetrafluoride and krypton in liquid fluorine.

bilities, tests were made to show the applicability

the temperature of satu- ration for a particular concentration. This method is illustrated in figure 3 for solutions of CF4 and krypton in fluo- rine. The minimum point in the saturated-solution curve for CF4 indicates the solid-solid transi- tion of CF4 at 76.09O K (ref. 8).

In method 3 solubil- ities were calculated directly from Raoult's law by the use of vapor- pressure-lowering meas- urements. This method was used only where sol- ubilities were small. Before Raoult's law was used to determine solu-

of the law. Applicability was shown by determining the vapor-pressure depression for unsaturated solu- tions at known concentrations that were near those of the saturated solutions.

The major factor in the experimental error for methods 1 and 2 was the accuracy with which the mole fraction of solute could be determined (-I-0.5 per- cent at higher concentrations to 51.3 percent at lower concentrations of sol- ute), while for method 3 the major factor was the accuracy of the Ap measure- ments (50.1 mm Hg).

RESULTS A N 3 DISCUSSION

For an ideal system the solubility of a solid in a liquid at tempera- ture T may be calculated from (refs. 2 and 3)

into account the change in the heats of fusion and transi- tion with temperature. The terms involving transition temperature Tt are used only for solutes with a solid-solid transition at a temperature greater

than T.

Since few systems behave ideally, equation (1) cannot be expected to give good predictions of solubilities. may be obtained if the regular solution concept is taken into consideration. Hildebrand (refs. 2 and 3) has presented for regular solutions an equation that takes into account the heat of mixing of solute and solvent:

More realistic predictions of solubilities

According to Hildebrand, the volume fraction cp may be expressed as

Since

and

then

Thus, equation (2) becomes

The solub'lity parameters 6j are defined in references 2 and 3 as 6. = ( -Ej/Vj)lf2. For low pressures -E may be replaced by the energy of vaporization AE, which may in turn be replaced by AHv - RT. Thus,

J

Since AHv,j point

is not often available at temperatures other than the boiling %,j, the change in the heat of vaporization with temperature must be

b

taken into consideration. This may be done by use of the Clausius-Clapeyron

.- c z-.

- 3 0 v,

- .- n

5 -

equation

6j =

the solubilities calculated from equation (3) by assum-

6- ing regular solutions, and the estimated experimental error at 77.5' K. ALSO in-

'-Argon

I I 1 I I I

fd In D\

( 5 )

Solubilities of CF4, C2F6, and C103F generally agree with values calcu- lated from equation ( 3 ) , although disagreement is noted for krypton and xenon

temperature in figure 5, as are the calculated results. The disagreement of krypton and xenon is unexpected and cannot be immediately explained. A com- parison of the NOZF solubility with calculated values is difficult because of the lack of a value for the heat of fusion. A heat of fusion of 700 cal- ories per mole was estimated for NOZF, however, from the relation of the heat of fusion to the melting point for several substances. With this value good agreement was obtained between calculated and experimental solubilities.

) solutions. Experimental solubilities for these solutions are plotted against

7

Method

0 1 0 2

3 Calculated Experimental

A

--- (a) Carbon tetrafluoride.

.6r

.1 I I I

.04

.01 .m I

(c) Perfluoroethane.

::I , .m1.

67 69

(b) Krypton. .02

. 0 1 ~ /*&+// I .m5- ,/AT$- , I I

73 75 77 79 81 67 69 71 73 75 77 79 81 u 1- I

Temperature, OK

71 H (d) Perchloryl fluoride. ( e ) Xenon.

Figure 5. - Solubilities in liquid fluorine.

Powdered tetrafluoroethylene polymer, SiF4, BF3, COF~, and A1F3 are all less soluble than can be determined by the experimental apparatus. These low solubilities agree with the calculations based on equation (3).

In the course of this investigation two liquid-liquid systems were stud- ied. The NF3-Fz system is nearly ideal throughout the entire composition range of 0 to 100 percent NF3 as determined by vapor-pressure measurements between 68' and 78' K. The nitrogen-fluorine system is completely miscible at 77.5' K. The results are as expected for these systems since the differences in 6 val- ues are small ( 6 ~ ~ -

Literature data on cryogenic solutions of solids in liquids are summarized in table I1 and are compared with values calculated from equation (3). The dif- ferences in 6 values and in molar volumes at 80' K, as well as the difference in van der Waal's constant b, are presented for comparison. Melting-point data, where available, and freezing-point (solubility) data are given for cases in which solid solutions are formed. When more than one reference gives data, what is considered the best value is presented.

= 1.82; 6w3 - 6 ~ ~ = 1.72).

t

The solubility of CF4 in fluorine reported in reference 1 appears to be

The reported solubility quite low (4.5 mole percent at 77.8O K), and is in disagreement with the value found in this study (86.7 mole percent at 77.5' K). was determined by observing the concentration at which a solid phase first ap- peared. It is suggested that perhaps some impurities were present in the re-

8

ported system and were mistaken for so l id CF4.

Some of t h e l i t e r a t u r e da ta agree with t h e calculated values, but many of t h e reported s o l u b i l i t i e s are considerably less than expected from equation (3). Pa r t i cu la r ly outstanding a r e the l o w s o l u b i l i t i e s of t he hydrocarbons i n l i q u i d oxygen. I n general , t he more unsaturated t h e hydrocarbon, t h e l a r g e r t h e per- centage deviat ion of t h e experimental da ta from t h e calculated values. cases where s o l i d solut ions are formed, t h e sol idus curve i s i n c loser agree- ment with calculated values than t h e l iqu idus or s o l u b i l i t y curve. Melting- point (sol idus) data , however, general ly a re l e s s than calculated values f o r l o w concentrations of solute , and the data approach t h e calculated values a t higher concentrations.

I n

It i s w e l l known t h a t s o l i d so lu t ions tend t o be formed by substances whose molecules a r e s i m i l a r i n s i z e and shape. If b as calculated from b = RTc/8PP, i s taken a s a measure of molecular s i ze , then t h e smaller t h e d i f - ferences i n b, t h e more l i k e l y t h e formation of a s o l i d solution. This i s in- deed t h e case, as indicated i n t a b l e I1 f o r known s o l i d solutions. cases, s o l u b i l i t i e s a r e l e s s than values calculated from equation (3). Thus, t h e s m a l l d i f ference i n b for t h e krypton-fluorine system suggests t h a t t h e low s o l u b i l i t y of krypton might be a t l e a s t p a r t i a l l y due t o t h e formation of a s o l i d solution. -

I n these

No other cor re la t ions were found between t h e deviat ions of experimental

Equation (3) can a t bes t be and reported s o l u b i l i t i e s from t h e calculated values and t h e molecular o r t h e physical p roper t ies of t h e so lu t ion components. expected t o give a general approximation f o r cryogenic s o l u b i l i t i e s even though i n some cases calculated and experimental values are i n good agreement.

Lewis Research Center National Aeronautics and Space Administration

Cleveland, Ohio, January 30, 1964

1.

2.

3.

4.

Kleinberg, S., and Tompkins, J. F.: The Compatibility of Various Metals with Liquid Fluorine. ASD TDR 62-250, 1962, Contract No. AF33(616) -6515, Air Products, Inc.

Hildebrand, J o e l H., and Scott, Robert L.: The Solubi l i ty of Nonelectro- lytes. 3rd ed., Relnhold Publishing Corp., 1950.

Hildebrand, J. H., and Scott, R. L.: Regular Solutions. PrentLce-Hall, Inc., 1962.

Faloon, A. V., and Kenna , W. €3.: The Preparation of Nitrosyl Fluoride and Ni t ry l Fluoride. J. Am. Chem. Soc., vol. 73, 1951, pp. 2937-2938.

9

5. Seaver, Robert E.: Analysis of Fluorine Gas by Reaction with Mercury. NASA TN D-1412, 1962.

6. Hu, 5. , White, D. , and Johnston, J. L. : Condensed G a s Calorimetry. V. H e a t Capacities, Latent Heats and Entropies of Fluorine from 13 t o 8 5 O K.; Heats of Tragsit ion, Fusion, Vaporization and Vapor Pressures of t h e Liquid. J. Am. Chem- Soc,, vol. 75, 1953, pp. 5642-5645.

7. Ja r ry , Roger L., and Miller, Henry C. : The Density of Liquid Fluorine I Between 67' and 103' K. J. h e r . Chem. Soc., vol, 78, 1956, pp. 1552- 1553.

8. Kostryukov, VI N,, Samorukov, 0. P. , and Strelkov, P. G. : Thermodynamic Studies at Low Temperatures, VII. Phase Transformation i n Sol id BF3, CF4, and SiF4. Zhur. Fiz . Khim. , vol, 32, 1958, pp. 1354-1361.

9. Fastovskii , VI, and Krest inski i , Y. Ar Solub i l i t y of Sol id Methane i n Liquid Nitrogen and Oxygen. Zhur. Fiz. Khim., vol. 15, 1941, pp. 525- 531.

10. Fedorova, M. F.: So lub i l i t y of Acetylene and Carbon Dioxide i n Liquid Nitrogen and Liquid Oxygen. Zhur. Fiz. Khim. , vol. 14, 1940, pp. 422- 426,

11. Tsin, N. M.z So lub i l i t y of Ethylene and Propylene i n Liquid Nitrogen and Liquid Oxygen, Zhur, Fiz. Khim., vol. 14, 1940, pp. 418-421.

12. Cox, Anna L. and D e V r i e s , Thomas: The So lub i l i t y of Sol id Ethane Ethylene, and Propylene i n Liquid Nitrogen and Oxygen. J. Phys. and CoUoid Chem., VOL 54, 1950, pp. 665-670.

13. Stackelberg, N, V., Heinrichs, Nagret, and Schulte, Werner: The So lub i l i t y of Krypton and Xenon i n Liquid Oxygen. 2. Physik Chem,, vol. A2.70, 1934, pp, 262-272.

14. Din, F. , and Goldman, K.: Solub i l i t y of Nitrous Oxide i n Liquid Oxygen. Trans, Faraday SOC., vol. 55, 1959, pp. 239-243.

15. Yunker, W. HI , and Halsey, G. D. : The Solubi l i ty , Act iv i ty Coefficient and H e a t of Solution of So l id Xenon i n Liquid Argon. 5. Phys. Chen, VOL 64, 1960, pp. 484-486.

16. Heastie, R.: Propert ies of Sol id and Liquid Solutions of Argon and Krypton. Proc. Phys. SOC. (London), vol. 73, 1959, pp. 490-500.

17. Veith, H. and Schroder, E.: Melting Diagrams of Several Binary Systems of Condensed Gases. Z. Physik. Chem., vol. fU79, 1937, pp. 16-22.

18. Omar, N. H., Dokoupil, Z., and Schroten, H. G. N.: Determination of t he Solid-Liquid Equilibrium Diagram f o r t h e Nitrogen-Methane System. Physics, vol. 28, 1962, pp. 309-329.

10

19. Din, F., Goldman, K., and Monroe, A. G. : Solid-Liquid Equilibriums of t h e Systems Argon-Nitrogen and Argon-Oxygen. Congr. Intern. Froid, ge, Par is , 1955. Compt. Rend. Tran. Com. I e t 11, pp. 1003-1010.

20. Fastovski i , V. G., and Kres t insk i i , Yu. A.f So lub i l i t y of Argon i n Liquid Oxygen. Zhur. Fiz. K h i m . , vol. 16, 1942, pp. 148-151.

21. Aoyama, Shin-ichi, and Kanda, Eizo: Fluorine at Low Temperature- 111. So lub i l i t y of Chlorine i n Liquid Fluorine. J. Chem. SOC. Japan., VOL 58, 1937, pp. 714-716.

22. Fedorova, N. F.: Binary Mixtures of Substances Melting a t Low Tempera- tures. Zhur. 'Eksptl'i Teoret- F i z - , vol. 8, 1938, pp. 425-435.

23. Stackelberg, M. V., Quatram, F., and Antweiler, H. J.: Mixed Crystals of Methane and Krypton. Z. Elektrochemie, vol. 42, 1936, pp. 552-557.

11

I- -

f

12

70.0

~xp. IEq. (1)IEq. (3)

72.0 74.0 76.0 77.5 error parameter, AV constant, 62 - 61, ml/mole Lb

Exp. IEq. (1)IEq. (3) Exp.lEq. (1)IEq. (3) mP. 1%. (1)IEq. (3) ExPo /Eq. (1)IEq. (3) ml/mhe

Aluminum trifluoride

TABLE I. - EXPERIMENTAL SOLUBILITIES OF SUBSTANCES IN LIQUID FLUORINE

0.77

.67

.47

1.69

3.67

4.80

1.77

4.68

__-

_ _ _ ---

Carbon tetrafluoride 0.652 I 0.622 0.616 0.705 0.697 0.692 0.763 0.775 0.772 0.850 0.857 0.855 0.867 0.875 0.874 i0.005

?.OOlO

? .003

i .0006

_+ . 0005

36.4 1,2 15.8

45.2

6.4

13.4

26.3

6.9

26.7

11.7

_ _ _ _ _ _ ---

Perfluoro- ethane _ _ _ ---

Krypton ,188 ,372

Xenon .0061 .176

--- .0142 ,0165 ,0154 ,0186

,369 ,216 .397 .392 ,240

.139 .0075 .189 .149 ,0091

,0212 .0197

.422 .417

.203 .159

.0240 .0270

.269 .447

.0111 .217

.0249 .0287 .0321

.442 .286 .466

,170 .0128 .227

.0295

.461

.178

.0024

.0014

. 0001

.0004

_--

_--

--- -

59.6 3

12.6 1,2

24.2 3

Perchloryl

Nitryl

Silicon

Boron

fluoride __-

fluorideb ---

tetrafluoride ---

trifluoride --- TFEPC

,0860 .0017 .0024 .lo02 .0021 .0033 .1118 44.4

.0012 .0012 .284

53.4

27.5

--_ I

_-- I _ _ _

1 I

TABLE 11. - SOLUBILITIES

Temperature, T, OK

85.0

Ref. I Eq. (3 ) Ref. 1 Eq. (3) I S o l u b i l i t y , x2, mole f r a c t i o n of s o l u t e

_ _ _____- I. 000245

.276

.793

.e60

---___-- .219

.0000031

.0000054

.000000I

.0107

_ _ _ _ _ _ _ _ _ _

:. 000001

,178

.923

_ _ _ _ .545

_ _ _ _ _ _ _ _ _ _ _ _ .920

Solu te

Methane

Acetylenet

Ethyleneb

Ethane

Propylenet

Krypton

Xenon

Carbon dioxidet

Nitrous oxide

Acetylenet

Ethylene

Ethane

Propyleneb

Carbon dioxidet

Xenon

Methanec

Krypton'

Krypton'

Ye thaneC

4rgonc

9rgonc

Zhlor ine

:arbon t e t r a - f l u o r i d e

3ul fur hexa- f l u o r i d e

iydrogen f l u o r i d e -

' A t 80' K.

Solvent

lxygen

'1 trogen

I rgon

rgon l i q u i d u s

s o l i d u s

rgon l i q u i d u s

s o l i d u s

l i q u i d u s

s o l i d u s

ethane

i t r o g e n l i q u i d u s

s o l i d u s

i t r o g e n li qu i dus

s o l i d u s

xygen l i q u i d u s

9011dU9

l u o r i n e

l u o r i n e

l u o r i n e

l u o r i n e

70.0 75.0

R e f . ( E q . ) 1 R e f . I Eq. (3 )

1.685

.000001

.0018

- -_____

.0077

.22

- - - - - - -

.000002:

.000015

.000001:

.0014

,0057

.0071

.000003

- -_ - - - -

--- - - - - _ _ - - _ _ _ _- - - -_ - - - - - - __

1.792

.000034

,114

--- - - - - - .341

.430

_ _ - _ _ - - - . 000000

. 000000

:. 000000

.0050

.0287

.0019

:. 000001 _ _ - - - - - - . - - - - - - - . - - - - -_ -

,812

.824

)Change i n hea t capac i ty terms not used i n equntior, ( 5 ) . >3o l id s o l u t i o n s a r e dnown t o form.

1.0056

.045

:.001

:.005

_ _ _ _ - - -. I. 00000:

.0038

.026

.024

.31

.115

. OOOOOt

.00003€

.000001

.0032

.0103

.023

. 00000:

_ - _ _ - -.

. 6 6

.84

__-

_ _ _ _-- __-

.71

.84

.86

.97

.82

.92

_ _ _

---

---

__-

- - -- ).000103

,178

.598

.603

.493

.192

.0000011

.000001:

. 000000:

.0075

,0384

.0027

.000001

- - - - - - -

.a57

-___ _ _ _ _ _ _ _ _ ___- _ _ _ _ .e49

_ _ _ _ .920

_ _ _ _ .923

---- _ _ _ _

_ _ _ _

_---

__-_

- __ - - - - I. OOOOO?

.0075

.OS4

.175

.010)

--_ _ _ _ - . 1 7 0

,000003

.000074

.000002

.0060

____- ___-_

.000004

.044

.81

.92

.10

.33

_ _ _ _ _ _

.86

.92

_ _ _ _ _ _ -_- __-

_ _ _

_ _ _

__-

_ _ _

14

t

O l V E N I N HOhEHENCES

95.0

R e f . I Eq. (3) R e f . I Eq. (3) I 100.0 -

Lfferences In solu- b i l i t y

srameter, 52 - 611 cal/cc) 112

0.33

5.44

1.96

1.59

2.20

(a)

0.57

1.69

5.74

7.32

7.30

3.82

3.45

4.05

7.60

2.14

.12

1.02

.83

1.53

__--

1.36

_ _ _ _

.46

_ _ _ 3.46

.77

_ _ _ 13.79

Dir- 'erence I molar ilume, A v .

i/mole

( a )

8.9

5.2

4.4

10.0

16.7

3.9

8.8

.2

2.3

13.5

3.9

1.8

8.4

8.4

8.1

8 . 2

3.2

5 .0

.6

7.6

.7

16.4

15.8

_ _ _ _

9.5

l f f e r e n c s in van er Waal' f ona tant,

Ab l/moie

10.9

19.2

26.1

33.1

50.3

7.6

19.2

11.0

12.4

12.5

19.4

26.5

43.6

4.3

18.9

10.6

7.3

3.3

4.2

6.4

.3

29.5

36.4

_ _ _ _

Data from

' e f . .

9

10

11

12

11 12

13

13

10

14

10

11

12

1 1

10

15

22

17

17

1 3

22

32

21

1

1

1

._

t h e r data in

ef.

~~

12

1 7

16

21

l , i

1.

7,1.

NASA-Langley, 1964 E-2343 15

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