22nd PICHE Review session – LAGUNA ChapterEVALUATION EXAMINATION

PHYSICAL AND CHEMICAL PRINCIPLESJuly 19, 2007

1. Tha maximum number of phase in equilibrium that can exist for a pure substance isa. 1 b. 2 c. 3 d. 4 e. 5

2. Calculate heat of vaporization of water having the normal boiling point and the vapor pressure of 23.76 mmHg at 25°C.

a. 42.7 kJ/mol b. 47.7kJ/mol c.47.2kJ/mol d. 157.7 kJ/mol e. None of the above3. The henry’s Law constant for carbon dioxide in water is 0.167 x 109 Pa at 25°C. Calculate the

solubility of carbon dioxide in water at 25°C in moles per liter at a partial pressure of carbon dioxide over a solution of 1.00 atm. Assume that a liter of solution contains 1000 g of water.

a. [CO2] = 3.73 x 10-2M d. [CO2] = 13.73 x 10-2Mb. [CO2] = 3.37 x 10-2M e. None of the abovec. [CO2] = 13.37 x 10-2M

4. At 20°C, the vapor pressures of pure benzene and toluene are 74 torr and 22 torr, respectively. A solution consisting of 1.00 mol of each component is boiled reducing the external pressure below the vapor pressure. Calculate the composition of the first trace of vapor formed.

a. in the vapor phase, Xbenzene = 1.77 and Xtoluene = 0.23 b. in the vapor phase, Xbenzene = 2.77 and Xtoluene = 0.33c. in the vapor phase, Xbenzene = 0.77 and Xtoluene = 0.23d. in the vapor phase, Xbenzene = 7.77 and Xtoluene = 0.023e. None of the above

5. The first order gasous decomposition of N2O4 and NO2 ha a Ka value of 4.5 x 103 s-1 at 1°C and an energy of activation of 58 kJ/mol. At what temperature will the rate constant be 1.00 x 104 s-1?

a. 823K b. 283 K c. 382 K d. 388 K e. None of the above6. Consider the cell

Zn(s)|ZnCl2 (a = 0.0050m, aq)|HgCl2(s)|Hg(l)|Pt(s)

In which the measured cell potential is 1.23 V. At 25°C, calculate the standard cell potential and the change in the Gibb’s fre energy.

a. E° = 1.61 V; ∆G = -273 kJb. E° = 11.61 V; ∆G = -732 kJc. E° = 1.16 V; ∆G = -237 kJd. E° = 2.16 V; ∆G = -137 kJe. None of the above

7. The following data about the final rates were obtained for the stoichiometric reation3A + B 2P

Experiment [A]0 (M) [B]0 (M) d[A]/dt (M/s)1 0.20 0.20 -1.2 x 10-8

2 0.20 0.60 -1.2 x 10-8

For the third experiment, a plot of 1/[A] against t was found to be linear. What is the order of the reaction with respect to A and B.

a. 1st order with respect to A; zero order with respcect to Bb. 2nd order with respect to B; zero order with respcect to Ac. 2nd order with respect to A; zero order with respcect to Bd. 3rd order with respect to A; zero order with respcect to Be. None of the above

8. Knowing that the Ksp of AgCl is 1.1 x 10-10 at 25°C, calculate the potential in Ag|Ag+ electrode

immersed in a 1.00 M KCl solution at 25°C. The standard reduction potentail of Ag|Ag + electrode is 0.799 V.

a. 0.702 V b. 0.207 V c. 2.2707 V d. 12.712 V e. None of the above9. At 300 K, the vapor pressure of dilute solutions of HCl in liquid GeCl4 are as follows:

XHCl 0.005 0.012 0.01932.0 76.9 121.8

Calculate for the Henry’s Law constant of HCl at 300 K.a. KHCl = 46.4 Mpa c. KHCl = 6.4 Mpa e. None of the aboveb. KHCl = 64.4 Mpa d. KHCl = 16.4 Mpa

10. The vapor pressure of dicholoromethane at 24.1°C is 400 torr and its enthalpy of vaporization is 28.7 kJ/mol. Estimate the temperature at which the vapor pressure is at 500 torr.

a. T = 303.07 K d. T = 133.77 Kb. T = 333.07 K e. None of the abovec. T = 333.70 K

11. The vapor pressure of benzene between 10°C and 30°C fits the expression ln P = 18.332 – 4009(1/T) where P is in torr and T in K. Calculate the molar enthalpy of vaporzation and the normal boiling point of benzene.

a. ∆Hvap = 143.08 kJ; normal BP = 355.39 Kb. ∆Hvap = 134.08 kJ; normal BP = 135.39 Kc. ∆Hvap = 34.08 kJ; normal BP = 350.39 Kd. ∆Hvap = 43.08 kJ; normal BP = 35.39 Ke. None of the above

12. Co-precipitation of impurities bu occlusion maybe reduced bya. washing a volatile electrolyteb. stirring the solutionc. precipitation from dilute solutiond. digestion

13. Oxalic acid can be determined gravimetrically by precipitation as Ce2(C2O4)3. xH2O and ignition to CeO2 for weighing. The gravimetric factor for conversion of CeO2 (FM 172.1) to H2C2O4 (FM 90.03) is

a. 90.03172.1

c. 2(172.1)3(90.03)

e. None of the above

b.172.190.03

d. 3(90.03)2(172.1)

14. A 0.7406-g sample of impure magnesite, MgCO3, was decomposed with HCl. The liberated CO2 was collected on calcium oxide and found to weigh 0.1881 g. Calculate the % Mg in the sample. (FM MgCO3 = 84.31, CaCO3 = 100.09)

a. 61.7% Mg c. 66.17% Mg e. None of the aboveb. 7.16 % Mg d. 6.17% Mg

15. A 0.728-g sample of iron ore is dissolved in acid. The iron is oxidized to the +3 state and then precipitated as Fe2O3.xH2O. The precipitate is filtered, washed and ignited to Fe2O3. The obtained solid weighs 0.314 g. Calculate the % Fe in the sample. (Molar Masses Fe = 55.85, O = 16)

a. 29.18% c. 30.2% e. None of the aboveb. 30.12% d. 23.3%

16. The phophorus in 0.2374-g sample was precipitated as the slightly soluble (NH4)3PO4.12MoO3. This precipitate was filterd, washed and the redissolved in acied. Treatment of the resulting solution with excess Pb2+ resulted in the formation of 0.2752-g PbMoO4. Determine the %P2O5 in the sample. (FM P2O5 = 141.995, PbMoO4 = 367.14, (NH4)3PO4.12MoO3 = 1876.34)

a. 1.968% P2O5 c. 1.868% P2O5 e. None of the above

b. 1.888% P2O5 d. 1.786% P2O5

17. Calculate the formality of a concentrated HCl solution (FM = 36.4561) given that the density is 1.18 g/mL and the percent mass is 36.0.

a. 11.7 F b. 17.7 F c. 12.7 F d. 16.7 F e. None of the above18. According to the CRC Handbook of Chemistry and Physics, the ionization caonstant of water at 60°C

is 9.25 x 10-14. At this temperature, pure water a. has a pH of 6.517b. has a pOH of 7.483c. is slighty acidicd. has a pH of 7.00, since pure water is always neutrale. a, b and c

19. Calculate the pH of a 1.0 x 10-8 M HCl solutiona. 9.68 b. 6.98 c. 7.89 d. 6.89 e. None of the above

20. The pH at the equivalence point int he titration of a 0.010-molar solution of a weak acid, HA< with pKa = 4.0, with 0.010-molar solution of NaOH is

a. 4.0b. greater than 4.0 and less than 7.0c. 7.0d. greater than 7.0e. not calculable because the initial volume of the weak acid solution is not given

21. An indicator has a Ka equal to 8 x 10-7. What is the ratio of the concentration of the acid form of the indicator to the concentraiton of the base form, in a buffer solution in which the [H+] is 1 x 10 -6 M?

a. 1/80 b. 1/8 c. 0.8/1 d.1/0.8 e 8/122. Which indicator would likely be most appropriate for use in weak acid titration?

(Transition ranges for each indicator are given in parentheses)a. bromocresol green (3.8 – 5.4)b. bromothymol blue (6.5 – 7.6)c. phenolphthalein ( 8.3 – 10.0)d. all of the above

23. Which of the folowing combination of solutes can srve as buffer mixtures?a. NH4Cl + NH3 in 1:1 mole ratiob. HCl + NaCl in 1:1 mole ratioc. NaOH + CH3COOH in 1:1 mole ratiod. NaOH + CH3COOH in 2:1 mole ratio

24. A 0.2076-g sample that might contain NaOH, NA2CO3 and NaHCO3 or any of their binary mixtures is titrated with 0.1062 M HCl by the double indicator method. It is found that 13.46 mL of the acid is required to reach the phenolphthalein endpoint. Methyl orange is then added to the solution and the titration continued using an additional 4.28 mL of the acid. Identif y and calculate the weight percentage of each component of the mixture. (FM Na2CO3 = 105.99, NaHCO3 = 84.00, NaOH = 40.00)

a. 13.18 % NA2CO3 and 17.77% NaOHb. 23.18 % NA2CO3 and 18.77% NaOHc. 33.18 % NA2CO3 and 17.78% NaOHd. 3.18 % NA2CO3 and 6.77% NaOH

25. A 100-mL sample of H2O containing Ca2+ and Mg2+ is titrated ith 15.28 mL of 0.01016 M EDTA in an ammonia buffer at pH 10.0. Another sample of 100 mL is titrated with NaOH to precipitate Mg(OH) 2

and then titrated at pH 13 with 10.43 mL of the same EDTA solution. Calculate the concentration of CaCO3 and MgCO3 in the sample in ppm. (FM CaCO3 = 100.09, MgCO3 = 84.31)

a. 108 ppm CaCO3 and 51.5 ppm MgCO3

b. 109 ppm CaCO3 and 14.5 ppm MgCO3

c. 106 ppm CaCO3 and 41.5 ppm MgCO3

d. 166 ppm CaCO3 and 42.5 ppm MgCO3

26. If 50.0-mL sample of water required 6.40 mL of EDTA solutiion for titration and each mL of EDTA solution is equivalrnt to 0.40 Mg2+, what is the hardness of water expressed as ppm CaCO3?

a. 218 ppm CaCO3 c. 812 ppm CaCO3 e. None of the aboveb. 182 ppm CaCO3 d. 128 ppm CaCO3

27. PbC2O4 and Mg(OH)2 have almost equal values of their Ksp’s. Therfore,a. Mg(OH)2 is more soluble than PbC2O4

b. Mg(OH)2 is less soluble than PbC2O4

c. PbC2O4 and Mg(OH)2 have equal solubilitesd. PbC2O4 and Pb(OH)2 have equal Ksp’s too

28. A 0.5012-g sample contains 34.14% KCl and 65.18% NaCl. How many mL of 0.1102 M of AgNO 3 will be required for the titration of this sample?

a. 71.56 mL c. 715.56 mL e. None of the aboveb. 17.65 mL d. 171.56 mL

29. Which species is responsible for the tinge of blood-red color at the endpoint for the Volhard method?

a. Ag2CrO4 b. FeSCN2+ c. AgCl d. FeCl3 e. AgSCN30. An excess KI is added to a sloution of K2Cr2O7 and the liberated I2 is titrated with 48.40 mL of 0.1000

N Na2S2O3. How many grams of K2Cr2O7 fid the chromate solution contain? (FM K2Cr2O7 = 294.2)a. 0.2393 g b. 2.293 g c. 22.293 g d. 1.293 g

31. A solution of KHC2O4 is 0.1000 N as an acid. What is its normality as a reducing agent?a. 0.3000 N b. 0.2000 N c. 0.1000 N d. 0.0500 N e. 0.4000 N

32. A sample of iron wire, 99.50% pure and weighing 0.2000 g is dissolved in HCl the Fe (II) is oxidized to Fe (III) with 0.1056 N KmnO4. The endpoint is overstepped in the addtion of 40.00 mL of the titrant. The solution is backtitrated using 3.25 mL of FeSO4 aolution. To a faint pink endpoint. Calculate the concentration of the FeSO4 solution used.

a. 2.2033 N b. 0.5233 N c. 0.2033 N d. 1.203333. A 25.0 mL aliqout of vinegar was diluted to 250 mL in a volumetric flask. Titration of 50.0 mL aliqouts

of the diluted soltion required an average of 34.88 mL of 0.09600 N NaOH. Express the acidity of the vinegar in % (w/v) of acetic acid

a. 5.22 % acetic acid (g/mL)b. 4.92 % acetic acid (g/mL)c. 4.02 % acetic acid (g/mL)d. 6.02 % acetic acid (g/mL)e. None of the above

34. Which of the following pairs does not constitute a buffer system?a. HPO4

2-/PO43- d. H2PO4

-/HPO42-

b. H2PO4-/HPO4

2- e. None of the abovec. HPO4

2-/H2PO4-

35. This concerns the control of transboundary movements of hazardous wastes and their disposala. Basel Convention d. Swiss Protocolb. Kyoto Protocol e. None of the abovec. Montreal Protocol

36. Express 250 ppb in ppma. 250,000 b. 25,000 c. 0.025 d. 0.25

37. Gasoline with an octane rating of 91 has the same engine performance as a mixture of 9% ________ and 91% ___________.

a. 2,2,4-trimethylpentane; n-hexadecaneb. n-heptane; 2,2,4-trimethylpentanec. n-hexadecane; 2,2,4-trimethylpentaned. 2,2,4-trimethylpentane; n-heptane

38. Which of the following is the standard method for measuring nitrates as nitrogen?a. stannous chloride methodb. cold vapor methodc. bruccine methodd. gas electrode method

39. Anna analyzed a sample and found the following results: Total solids = 250 mg/L; Fixed suspended solids = 40 mg/L; and Total disssolved solids = 120 mg/L. Approximate what percent of the solids are composed of organc matter.

a. 36 b. 52 c. 64 d. 4840. What is the total N concentration (mg/L) of a water sample with three nitrogen species with the

following amounts? [NO3] = 8 mg/L; [NO2] = 4 mg/L and [NH3] = 25 mg/La. 21.8 b. 23.6 c. 3.02 d.22.4

41. A water sample has the following chemical composition: [Na+] = 15 mg/L; [K+] = 10mg/L; [Ca2+] = 20 mg/L ; [Mg2+] = 10 mg/L; [SO4

2--] = 25mg/L and [Fe2+] = 5 mg/L. What is the total hardness in units of mg/L of CaCO3?

a. 99 b. 105 c. 108 d. 10242. A wastewater sample (10mL) was analyzed for its BOD content. Using the standard BOD test, the

initial dissolved oxygen was measured at 7.8 mg/L. After 5 days it was measured at 4.5 mg/L. After 10 days, it was 4.3 mg/L. And at 21 days, it was 4.2 mg/L. Approximate the ultimate BOD of the sample in mg/L.

a. 99 b. 105 c. 108 d. 10243. This is the Philippine Clean Water Act of 2004

a. RA 9275 b. RA 9003 c. RA 8749 d. RA 696944. DAO 2004-01 is the Chemical Control Order for what substance?

a. asbestos b. cyanide c. mercury d.Polchlorinated biphenyls45. From the following equations and heat reaction, calculate the standard molar heat of formation of

AgCl at 25°C.Ag2O(s) + HCL(g) 2 AgCl(s) + H2O(l) ∆H° = -77610 cal2Ag + ½ O2 Ag2O(s) ∆H° = -7310 cal½ H2 (g) + ½ Cl2 (g) HCl(l) ∆H° = -22060 calH2(g) + ½ O2 (g) H2O(l) ∆H° = -68320 cal

a. -15.18 kcal/mol d. +15.18 kcal/molb. -30.36 kcal/mol e. None of the abovec. +30.36 kcal/mol

46. Air undergoes Joul-Thomson expansion from 20 atm to 1 atm pressure at 0°C. Calculate the final temperature of air, assuming that μJT is given by the equation: μJT = 0.266 – 8.95 x 10-4P

a. 272.9 K b. 373.15 K c. 265 K d. 268 K47. Take the nitrogen to be a Van de Waals gas (a = 10408 L2

atm/mol2 and b = 0.03913 L/mol). Calculate the change in ethalphy when the pressure on the gas is decreased from 500 atm to 1.0 atm at 300 K. Assume Cp,m = 7/2 R.

a. 3.73 kJ b. 37.55 kJ c. 1.73 x 103 kJ d. 19.5 kJ48. Suppose that an internal combustion engine runs on octane, for which the ethalpy of combustion is -

5512 kJ/mol and take tha mass of 1 gallon of fuel as 3 kg. What is the maximum height, neglecting all forms of friction, to which a 1000-lg car can be driven on 1 gallon of fuel? Given that the engine cylinder temperature is 2000°C and the exit temperature is 800°C.

a. 5.5km b. 78 km c. 15.6 km d. 3.9 km49. A sample of perfect gas that initially occupies 15.0 L at 250 K and 1.00 atm is compressed

isothermally. To what volume muts the gas be decreased i order to reduce its entropy by 5.0 J/K.a. 6.6 L b. 3.3 L c. 10.0 L d. 15.3 L

50. Calculate the pressure for 1.00 mol of argon at 0°C and 5.00dm3 using the Dieterici equation ( a = 1.75 dm6 bar/mol; b = 0.035 dm3 bar/mol)

a. 3.54 bar b. 5.52 bar c. 4.50 bar d. 2.53 bar51. Calculate the ratio of vrms of 235UF6 at room temperature

a. 0.996 b. 1.354 c. 0.758 d. 1.06152. The cubic expansion coefficient (α) of water at 26°C is 2.57 x 10-4 K-1, and the isothermal

compressibility (ĸ) is 45.24 x 10-6 bar-1. Given that the density of water is 0.997075 x 103 kg/m3, calculate Cp – Cv.

a. 3.44x 10-3 J/mol-K c. 0.521 J/mol-Kb.0.445 J/mol-K d. 0.786 J/mol-K

53. Consider a 1.00-kg of iron at 99°C placed in contact with a 1.00-kg block of iron at 25°C. What is the temperature of the final state of the system. ( cp, iron = 444 J/K-kg)?

a. 62°C b. 85°C c. 93°C d. 57°C54. A system recieves 75 J of electrical work, delivers 274 J of expansion work, and absorbs 168 J heat.

What is the internal energy change of the system?a. -31 J b. 199 J c. -199 J d. -93 J

55. Site of photosyhthesis _____________56. Powerhouse of the cell ____________57. Regulates the flow of metbolites to and from the cell __________

For numbers 58 to 60, consider the choices below:a. lactose b. starch c. sucrose d. glycogen e. fructose

58. a ketohexose _________59. a reducing disaccharide _________60. sotrage polysaccharide in animals __________

For numbers 61 to 63, chose the compound that best fits the given description:a. nucleotide c. uracil e. thymineb. ribose d. deoxyribose

61. the sugar moiety in DNA __________62. pyrimidine derived base present only in DNA ___________63. a molecule consisiting of a nitrogenous base, a sugar and a phosphate group

For numbers 58 to 60, consider the following biomolecules:a. carbohydrates c. proteinsb. lipids d. nucleic acid

64. its backbone consists of alternating sugar and phophate groups ___________65. group of biomolecules where fats and oils belong ___________66. Heat, pH extremes and some organic solvents can cause proteins to

a. hydrolyze c. denatureb. dissolve d. decompose

67. Competetive inhibiiton is best overcome by _____________a. increasing [Enzyme] c. increasing [Substrate]b. increasing [Product] d. all of the above

68. Enzymes as catalysts accomplish which of the following energy effects?a. Raise the energy of activiation d. Decrease the free energy of the reactionb. Lower the energy of activationc. Raise the energy level of the products

69. Which of the values below is the ratio of conjugate base to acid when pH of the solution is equal to the pKa of the weak acid?

a. 1 b. 2 c. 30 d. 6070. Which of the following structures is for the Zwitterion of alanine?

71. Which of the following bonds can be cleaved by a protease?a. glycosidic acid c. N-glycosyl bond b. phosphodiester linkage d. peptide bond

For numbers 72 to 75, consider the following choices:

72. most reactive towards electrophilic aromatic substitution73. does not undergo oxidation74. can undergo chlorination folllowing the free radical substitution mechanism75. can form intramolecular hydrogen bonds

For numbers 76 to 78, consider the following compounds:

76. an epimer of A77. a meso compound78. an enantiomer of C

For numbers 79 to 82, choose from the following compounds:

79. a tertiary amine80. can couple with a diazonium cation to form an azo compound

81. formed by the reaction between benzoyl chloride and methylamine82. an amino acid

For numbers 83 and 84, choose the appropriate characterization test for each pair of compounds below:

a. aqeous FeCl3 c. Na metalb. aqeous NaHCO3 d. hot KMnO4

83. phenol and cyclohexanol84. 1-pentene and 1-pentyne

For numbers 85 and 86, consider the following compounds:a. Glycine c.lysineb. Proline d. glutamic acid

85. a cyclic amino acid86. a basic amino acid

87. The theoretical gas composition of biogas during the anaerobic fermentation of organic waste water is:

a. 50% CH4, 50% CO2 by volume d. 60% CH4, 40% CO2 by massb. 60% CH4, 40% CO2 by volume e. none of the abovec. 50% CH4, 50% CO2 by mass

88. An enzyme-inhibitor complex (EI*) exists in what type(s) of inhibition?a. competitive inhibition d. (a) and (b)b. non- competitive inhibition e. (b) and (c)c. uncompetitive inhibition

89. Which of the following statements are false?a. blue green algae are photosynthetic prokaryotesb. yeasts belonging to the genus Saccharomyces are fungic. endoplasmic reticulum is a structure embedded in the ribosomes and play a role in protein synthesisd. (a) and (b)e. (a) and (c)

90. An enzyme which hydrolzes protein at acidic pH isa. trypsin b. chymosin c. pesin d. lipase e. bacteriocin

91. A microorganism which can utilize glucose as a carbon source but cannot grow in the dark is a:a. chemoautotroph d. chemoheterotrophb. photochemotroph e. photoheterotrophc. photoautotroph

92. Which of the following base pairs are not present in RNA?a. adenine-thymine b. guanine-cytosine c. adenine-uracil d. guanine-uracil

93. A 7.5 m3 chemostat operating at 75% capacity is producing biomass from a glucose feed at a volumetric flow rate of 46.9L/min. The specific growth rate of the microorganisms is

a. 0.373 per hour d. 0.006 per hourb. 0.0083 per hour e. none of the abovec. 0.5 per hour

94. In the alcoholic fermentation of cooked rice to wine (7% to 12% ethanol) (example, Japanese sake), which of the following microorganism(s) are used?

a. Aspergillus oryzae only d. Aspergillus oryzae and Saccharomyces cerevisiaeb. Aspergillus niger only e. Aspergillus niger and Saccharomyces cerevisiae

c. Saccharomyces cerevisiae only95. Which of the following pairs of symbols represent different isotopes?

96. Which ion is not correctly paired with its name?a. O2-, oxide ion c. SO3

2-, sulfiteb. Al3+, aluminum ion d. N3-, azide ion

97. Aluminum oxide (Al2O3) occurs in nature as a mineral called “corundum”, which is noted for its hardness and its resistance to corrosion. The density of corundum is 3.97 g/cm3. How many atoms of aluminum are there in 15.0 cm3 of corundum?

a. 7.03 x 1023 atoms c. 1.17 atomsb. 3.52 x 1023 atoms d. 1.38 x 1024 atoms

98. An unknown compound conatining carbon, hydrogen and chlorine has the following mass percentages: 18.00% C, 2.26% H and the rest Cl. What is its emperical formula?

a. C2H3Cl3 c. C2H2Cl3

b. C1H2Cl3 d. C2H2Cl2

99. Carbon Sulfide (CS2) is a liquid that is used in the production of rayon and cellophane. It is manufactured from methane and elemetal sulfur vai the balanced reaction CH4 + 4S CS2 + 2H2SWhat is the mass of CS2 that can be prepared by the complete reaction of 67.2 g of sulfur?

a. 76.14 g b. 39.9 g c. 80.0 g d. 20.0 g100. Heptane is always composed of 84% carbon and 16% hydrogen by mass. What law does this

observation illustrate?a. The Law of Conservation of Energyb. The Law of Conservation of Massc. The Law of Definite Proportionsd. The Law of Multiple Proportions