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Name CHEMISTRY 114 Spring, 2003

Signature

T.A. name FINAL EXAM

Monday, May 12, Version

STUDENT AFFILIATE #

1. Each student is responsible for following directions. Read this page carefully.

2. Write your name and other requested information on this page and on theseparate answer sheet.

3. CODE your name, LAST (FAMILY) NAME first on the answer sheet using anordinary (#2) pencil.

4. CODE your correct identification number (student affiliate ID 10 digits) on theanswer sheet. This is very important!

5. Put all calculations on the examination pages. DO NOT PUT ANY EXTRAMARKS ON THE COMPUTER ANSWER SHEET!

6. This exam consists of 50 multiple-choice questions worth 4 points each plusone bonus question. Choose the one best or most correct answer for eachquestion and write it both on your exam paper and on the computer answersheets. The computer answer sheet is the only one that will be graded!

7. This exam consists of 12 pages INCLUDING THIS page and a periodic table. Please check to be sure that you have them all!

Useful Information:Ideal gas constant, R = 8.314 J mol-1 K-1

= 8.205 x 10-2 liter atm mol-1 K-1

Molar volume of ideal gas at STP = 22.41 liter mol-11 litre- atmosphere = 101.3 J

760 torr = 1 atm pressure

Formula for hydrogen emission spectrum 1/λ = Rn nf i

1 12 2−

where R = 1.097 x 107 x m–1

T = t + 273.15

PV = nRT

∆ Ε = q + w

∆G = ∆H – T∆S

∆G° = -RT ln K

KP = Kc x (RT)∆n(gas)

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PART A: MATERIAL SINCE LAST EXAM

1. The stable structure of iron at standard temperature and pressure is:

A. simple cubic D. tetragonal close-packedB. HCP E. BCCC. FCC

2 and 3. Refer to the accompanying phase diagram for the following two questions.

2. At (or between) which tempererature(s) will the solid solution have thecomposition 20% B?

A. 610oC D. 550oCB. 550oC and 300oC E. 440oCC. 550oC and 610oC

3. Which of the following correctly describes the phases present in region "a"?

A. homogeneous liquid solution and solid BB. eutectic and solid BC. homogeneous solid solution and homogeneous liquid solutionD. solid solution of B in AE. homogeneous liquid solution

4. A mild steel contains 0.30 wt % C. What is the mole % of carbon in mild steel?

A. 0.025 D. 0.30B. 17.8 E. 1.1C. 1.4

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5. Which of the following molecules is an amine?

A. CH3 CH2 CN D. C6H5 NO2

B. CH3 CH2 CH2 NO2 E. CH2 CH CN

C. C6H5 NH2

6. Which of the following is the chemical link established in the formation of anester from an acid and an alcohol?

A.C C O C

OD. C C C C

B. C CN C

E. C C C C

Cl

C. C C N C

O H

7. For the reaction system:

Co O(s) + H2(g) Co(s) + H2O(g)

at 550°C, K = 67. The equilibrium constant expression is:

A.CoO H

Co H O[ ][ ][ ][ ]

2

2

D. H

H O2

2

[ ][ ]

B.Co H O

CoO H[ ][ ][ ][ ]

2

2

E. H O

H2

2

[ ][ ]

C.Co H O

H[ ][ ]

[ ]2

2

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8. Which of the following is not a natural polymer?

A. starchB. proteinC. celluloseD. polyesterE. all of these are natural polymers

9. What polymer is used to make bulletproof vests and protective clothing wornby firefighters?

A. polystyreneB. kevlarC. polyethyleneD. nylonE. polyisobutylene

10. Hydrocarbons containing carbon-carbon single bonds and no multiple bondsare called ________.

A. alkanesB. aromatic hydrocarbonsC. alkynesD. alkenesE. olefins

11. What is the formula for butane?

A. C2H6

B. C3H8

C. C4H10

D. C5H10

E. C6H6

12. In the smectic C liquid-crystalline phase, _________.

A. the molecules are aligned with their long axes tilted with respect to a lineperpendicular to the plane in which the molecules are stacked

B. the molecules are aligned along their long axes, with no ordering withrespect to the ends of the molecules

C. the molecules are arranged in sheets, with their long axes parallel andtheir ends aligned as well

D. disk-shaped molecules are aligned through a stacking of the disks in layersthe molecules are oriented in a totally random fashion

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13. For the following reaction at 25oC, Kc =3.0 x 105 . What is K p ? (use R = 0.0821 L.atm/K.mol)

2H2S(g) + 3O2(g) 2 H2O(g) + 2SO2(g)

A. 1.2 x 104

B. 8.2 x 10 –5

C. 3.3 x 10-6

D. 3.0 x 105

E. 7.3 x 106

14. Which one of the following will result in a shift of the ammonia formationequilibrium ( equation below ) to the left?

N2 (g) + 3 H2 (g) 2 NH3 (g) ∆H° = -92.2 kJ

A. high pressure and high temperatureB. low pressure and low temperatureC. high pressure and low temperatureD. low pressure and high temperatureE. none of these will cause a shift

15. Carbon disulfide and chlorine react according to the following equation:

CS2(g) + 3Cl 2(g) S2Cl2(g) + CCl4(g)

When 1.00 mol of CS2 and 3.00 mol of Cl2 are placed in a 2.00 liter container andallowed to come to equilibrium, the mixture is found to contain 0.250 mol ofCCl4. What is the amount of Cl2 at equilibrium?

A. 2.25 molB. 2.75 molC. 0.75 molD. 0.25 molE. 0.50 mol

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16. NOCl decomposes according to the equation

2NOCl (g) Cl2(g) +2NO(g)

Six mol of NOCl are placed in a 2.0 liter vessel, and after reaction, theequilibrium mixture is found to contain 2.0 mol NOCl. What is Kc for thisreaction?

A. 16B. 4.0C. 8.0D. 0.25E. 0.13

17. Which statement is true?

A. Collisions between molecules cease when a reaction reaches chemicalequilibrium.

B. A reaction may reach chemical equilibrium before the rates of the forwardand reverse reactions become equal.

C. Reactants are still transformed into products when a reaction reacheschemical equilibrium.

D. Products are no longer transformed into the original reactants when areaction reaches chemical equilibrium.

18. The reaction

A + B X + Y has Kc = 997 at 472 K. At equilibrium, __________.

A. products predominateB. reactants predominateC. roughly equal molar amounts of products and reactants are presentD. only products existE. only reactants exist

19. The effect of a catalyst on an equilibrium is to ___________.

A. increase the rate of the forward reaction only

B. increase the equilibrium constant so that products are favored

C. slow the reverse reaction only

D. increase the rate at which equilibrium is achieved without changing thecomposition of the equilibrium mixture

E. shift the equilibrium to the right

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20. Consider the following chemical reaction:

H 2(g) + I 2(g) 2HI(g)

At equilibrium, the concentrations of H2 , I2 , and HI were 0.15 M, 0.033 M, and0.55 M, respectively. The value of Kc for this reaction is __________.

A. 23B. 111C. 9.0 x 10-3

D. 6.1 E. 61

21. Which of the following substances is not in its standard state at 25°C and 1 atm?

A. H2O (l)B. N2 (g)C. Hg (s)D. Fe (s)E. C (graphite)

22. Calculate the standard entropy change, in J/K, for the following solid statetransition:

Sn(s) , white ⇒ Sn(s) , grey

if S° for Sn (white) = 51.55 J/mol.K and So for Sn (grey) = 44.10 J/mol.K.

A. 7.45B. -7.45C. 95.7D. -95.7E. 2.24 x 103

23. The stable state of a system is the state of lowest free energy. Which of thefollowing expressions relates the free energy to other properties that each phaseof a substance possesses.

A. G = H – TSB. G = T – HSC. G = S – HTD. G = HS – TE. G = E/nF

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24. For the reaction:

C2H6(g) C2H4(g) + H2(g)

∆H is 137 kJ and ∆S is 120 J/K

This reaction will be:

A. spontaneous at all temperaturesB. spontaneous only at high temperatureC. spontaneous only at low temperatureD. nonspontaneous at all temperaturesE. unreliable

25. Consider the following reaction at 25 oC :

C(s) + H2O(g) CO(g) + H2(g)

For this reaction, ∆Go = 91.2 kJ, ∆So = 135 J/K

What is the value of ∆Ho for this reaction at 25oC ?

A. 40.3 kJB. 226 kJC. 91.3 kJD. 131.4 kJE. 51 kJ

PART B: COMPREHENSIVE (exams 1 – 3)

26. Cathode rays are

A. streams of electronsB. positively charged particlesC. fast moving neutronsD. nuclei of a helium atomE. attracted to the anode

27. The neutral atoms of all the isotopes of the same element have

A. different numbers of protonsB. equal numbers of neutronsC. the same number of electronsD. the same mass numbersE. the same masses

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28. The nucleus of a radon atom, 86222Rn contains

A. 222 protons and 86 neutrons.B. 86 protons and 136 neutrons.C. 86 protons and 86 neutrons.D. 86 protons, 136 neutrons, and 86 electrons.E. 86 neutrons and 86 electrons.

29. The number of protons in the nucleus determines the

A. atomic mass.B. atomic number.C. mass number.D. number of neutrons.E. number of isotopes.

30. When the temperature of a sample of gas contained in a fixed volume of 1.5 liters at pressure 1.5 atm, is increased from 100oC to 250oC, the pressure:

A. decreases to 0.5 atmB. increases to 3.8 atmC. increases to 2.1 atmD. decreases to 1.15 atmE. remains the same

31. Which of the following sets of n,1, m1, and ms quantum numbers is notpermissible?

A. 1, 0, 0, 1/2 D. 2,1, 1, -1/2B. 4, 0, 0, 1/2 E. 2, 0, 0, +1/2C. 3, 3, -3, -1/2

32. The maximum number of electrons that can be accommodated in a p subshellis

A. 2 B. 4 C. 6 D. 8 E. 10

33. Show that you understand what a molecule is by answering the followingquestion. Which of the following substances will form a “molecular” solid?

A. C B. ZnCl2

C. SiO2

E. NaFF. P4

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34. In which of the following substances will hydrogen bonding play an importantrole in determination of the boiling point?

A. H2S D. HFB. CCl4 E. CH4

C. CHCl3

35. Which of the following processes may be ENDOTHERMIC or EXOTHERMIC?

A. condensationB. dissolutionC. freezingD. vaporizationE. sublimation

36. The geometry of the SO3 molecule is best described as?

A. linear D. tetrahedralB. trigonal planar E. trigonal pyramidalC. square planar

37. The F__N __ F bond angle in the NF 3 molecule is slightly less than _______.

A. 90o B. 109.5 o C. 120 o D. 180 o E. 60 o

38. H

C C

Cl

H Cl

H

C C

H

Cl Cl

H

C C

Cl

Cl H

x y z

The compound(s) which is (are) polar is(are)

A. x only. D. x and y.B. y only. E. x and z.C. z only.

39. How many liters of O2 (g) will be formed at standard temperature and pressureby the total decomposition of 10.0 liters of H2O(g) ?

A. 2.58 D. 5.0B. 2.50 E. 5.17C. 10.0

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40. All of the following are periodic functions of the atomic number except

A. atomic massesB. atomic radiiC. electronegativityD. electron affinityE. ionization energy

41. An element has the following set of properties: It is a gas in the pure state, butoccurs in great quantities in the sea. It can exhibit many oxidation numbers,including 5 and 7 but the commonest is -1. The element must be

A. N B. He C. O D. Cl E. M n

42. Which of the following elements will burn in chlorine to form an ionic compound?

A. B B. Na C. Si D. P E. S

43. Which of the following is an oxidation–reduction reaction?

A. Cu AgNO Ag Cu NOs s( ) ( ) ( ) ( ) ( )+ → +2 23 99 3 2 99

B. HCl NaOH H O NaCl aq( ) ( ) ( ) ( ) 99 99 2 1+ → +

C. AgNO HCl AgCl HNOaq aq3 99 5 3( ) ( ) ( ) ( ) + → +

D. Ba C H O Na SO BaSO NaC H Os( ) ( ) ( ) ( ) ( )2 3 2 2 99 2 4 99 4 2 3 2 992+ → +

E. H CO Ca NO HNO CaCOaq aq2 3 3 2 3 99 3 992( ) ( ) ( ) ( ) ( ) + → +

44. Of the following molecules, only one is non-polar. It is

A. CH4 D. HClB. H2O E. COC. NH2

45. Of the following substances, only ______ has London dispersion forces as theonly molecular force.

A. CH3OH D. CH4

B. NH3 E. HClC. H2S

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46. What is the volume of steam produced when 3 moles of water are converted tothe gas state at 100 ºC? Assume steam behaves as an ideal gas.

A. 22.4 l D. 91.9 lB. 44.8 l E. 61.2 lC. 32.2

47. What is the oxidation number of sulfur in the compound K2 SO 4 ?

A. + 2 D. + 5B. + 3 E. + 6C. + 4

48. Which of the following statements is not true about one component phase diagrams?

A. The highest temperature at which a liquid phase can exist is the critical temperature.

B. Both the liquid vapor pressure line and the melting point line must always have positive slopes.

C. When the temperature of a liquid is raised at a fixed pressure, the liquidwill boil when the vapor pressure reaches the value of the pressureacting on the system (the fixed pressure).

D. At the triple point three phases, gas, liquid, and crystal, are all equally stable.

E. The crystal/ vapor (sublimation) and the liquid/vapor lines, mustalways have positive slopes.

49. A vessel contained N2, Ar, He, and Ne. The total pressure in the vessel was 987torr. The partial pressure of nitrogen, argon, and helium were 44, 486, and 218torr, respectively. The partial pressure of neon in the vessel was ______torr.

A. 42.4 D. 239B. 521 E. 760C. 19.4

50. The direct conversion of a solid to a gas is called ___________.

A. fusion D. boilingB. vaporization E. sublimationC. condensation