acs exampractice

8/18/2019 ACS Exampractice

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General Chemistry II Sample Test bank Page 1of 18

1. According to the Bronsted—Lowry definition,which chemical species can function both as anacid and as a base?a. Cl —

b. SO42—

c. NH4+

d. HCO3 —

e. H3O+

2. In the reaction CN — + H2O !" HCN + OH —

which is an acid—base conjugate pair?a. H2O and HCNb. H2O and OH

— c. CN — and H2O

d. HCN and OH —

3. Given that HX is a stronger Bronsted acid thanHY in aqueous solution, which is true of a 1 Msolution of NaX

a. It is less basic than a 1 M solution of NaY.b. It is more basic than a 1 M solution of NaY.c. It yields a neutral solution.d. It is more concentrated than a 1 M solution

of NaY.

4. The pH of a 0.03 M HCl solution isa. 1.5b. 2.5c. 3.5

d. 12.5

5. The pH of a 1.0 x 10 —3

M Ba(OH)2 solution at25

oC is

a. 2.7

b. 3.0c. 11.0d. 11.3

6. Which is the strongest acid?

a. HClOb. HClO2c. HClO3

d. HClO4

7. Which salt reacts with water (hydrolyzes) to

produce a basic solution?

a. NaC2H3O2 b. NaNO3 c. NH4Cld. BaSO4

8. The weakest of the bases listed is

Acid ConjugateBase

Ka (IonizationConstant of Acid)

HCl Cl — 100% ionized

HSO4 — SO4

2— 1.2 x 10-2

H2S HS — 5.7x10-8

HS — S2— 1.2x10-13 a. Cl —

b. CN — c. HS — d. S2— e. SO4

2—

9. The oxide of which element will react with waterto form the strongest acid?

Main Groups

Period I II II

I

IV V VI VII O

First

Second X Y Z P Q S U

Third W R T M

a. Wb. M

c. Pd. Re. Z

10. Which statement is a logical inference from

the fact that a 0.10 M solution of potassiumacetate KC2H3O2, is less alkaline than a 0.10 Msolution of potassium cyanide, KCN?

a. Hydrocyanic acid is a weaker acid than

acetic acid.b. Hydrocyanic acid is less soluble in water

than acetic acid.c. Cyanides are less soluble than acetatesd. Acetic acid is a weaker acid than

hydrocyanic acid

11. In the titration of 50.0 mL of 0.100 M benzoic acid (a monoprotic acid) with 50.0 mL of0.100 M NaOH, the properties of the solution at

the equivalence point will correspond exactly tothe properties ofa. a 0.100 M sodium solution.b. a 0.0500 M sodium hydroxide solution.c. a 0.0500 M benzoic acid solution.

d. a 0.0500 M sodium benzoate solution.


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12. A mixture of which pair of 0.1 M aqueoussolutions would constitute a buffer?a. NaOH and NaClb. HCl and NaOH

c. HCl and NaCld. NH3 and NH4 NO3

13. What do these have in common?20 Ne 19F1- 24Mg2+

a. the same number of protonsb. the same number of neutronsc. the same number of electronsd. the same size

14. The number of neutrons in the nucleus of

an atom of 1327

Al isa. 40b. 13

c. 27d. 14e. 9

15. The orbitals of 2p electrons are often

represented as beinga. elliptical.b. Pyramidalc. Tetrahedrald. dumbbell shaped

e. spherical.

16. The element in Period 5, Group 3A, has theouter electron configurationa. 5s25p1

b. 3s23p5 c. 3s23p3

d. 5s25p3

17. Which electron configuration is

impossible?

a. 1 s22s22p6 3s2 b. 1s22s22p63s23p6 c. 1s

22s

22p

62d

2

d. 1s2

2s2

2p5

3s1

18. The element X occurs naturally to the

extent of 20.0% 12X and 80.0% 13X. The atomicmass of X is nearest

a. 12.2b. 12.5c. 12.8d. 13.0

19. Which electron transition is associated withthe largest emission of energy?

a. n=2 to n=1

b. n=2 to n=4c. n=2 to n=3d. n=3 to n=2

20. If an electron moves from one energy level

in an atom to another energy level more remotefrom the nucleus of the same atoma. energy is absorbed.b. energy is liberated.c. there is no energy change.

d. the atom must assume a different ionicvalence

e. light of a definite wave length is emitted.

21. A photon of light of 450 nm, when

compared to light of wavelength 300 nm, has(1nm = 10-9 m)

a. a higher frequency.b. lower energy.

c. a greater velocity.d. a shorter wavelength

22. Which set of quantum numbers is possiblefor an electron in an atom?

a. n=3, l=0, ml =1, m s = -½

b. n=2, l=2,ml = -2, m s = -½c. n=5, l=2, ml =2, m s =+½d. n=4, l=3, ml = -4, m s= -½

23. A compound consisting of an element

having a low ionization potential and a secondelement having a high electron affinity is likelyto have

a. covalent bondsb. metallic bondsc. coordinate covalent bonds

d. ionic bonds.

24. According to modern bonding theory the

number of sigma (σ) and pi (π) bonds in theethylene molecule H2C=CH2 is

a. l π and 4 σ

b. l π and 1 σ

c. l π and 5 σ

d. 2 π and 4 σ

e. l π and 6 σ


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25. The number of σ bonds in N=N isa. 1b. 2c. 3

d. 4

26. The elements in an ionic compound are

held together by

a. electrostatic forces of attraction.b. van der Waals forcesc. the spin of paired electrons.d. the formation of hybrid orbitals.e. an electron pair.

27. In every electrolytic and galvanic (voltaic)cell the anode is that electrode

a. at which oxidation occurs.

b. which attracts cations.c. at which electrons are supplied to the

solution.d. at which reduction occurs.

28. Metal X was plated from a solutioncontaining cations of X. The passage of 48.25 Cdeposited 31 mg of X on the cathode. What is the

mass of X (in grams) per mole of electrons?a. 47b. 62c. 93

d. 186

29. In a galvanic (voltaic) cell in which thereaction is Cd + Cu

2+" Cu + Cd

2+ and the ions are at unit concentration (activity),

the cell potential is

Cd" Cd2+

+ 2e- 0.4021 V

Cu" Cu2+ + 2e- - 0.344 Va. 0.1383 V

b. 0.4021 Vc. 0.344 V

d. 0.7461 Ve. 0.3677 V

30. In which reaction will an increase in total pressure at constant temperature favor formationof the products?a. CaCO3(s)!" CaO(s) + CO2(g)b. H2(g) + Cl2(g)!"""" 2HCl(g)

c. 2NO(g) + O2(g)!" 2NO2(g)d. COCl2(g)!" CO(g) + Cl2(g)

Standard Potentials Eo

Mg" Mg2+

+2e 2.37V

Al" Al3++3e 1.66V

Zn" Zn2++2e 0.76V

Fe"Fe2+

+2e 0.44V

Cu" Cu2++2e 0.34V

Ag" Ag++ e -0.80V

31. Using only the metals Mg, Al, Zn, Fe, Cuand Ag, together with their 1 M salt solutions, avoltaic cell of the highest possible voltage would

be constructed using electrodes of these metals.a. Mg and Agb. Mg and Fec. Zn and Cud. Al and Age. Mg and Al

32. E = Eo - 0.059/n log Q (Nernst equation)

[H+] = 1.0 M initially, P 02 = 1.0 atm

4e + O2(g)+4H+(aq)!" 2H2O(l) E

o=1.23V

Based on the information above, which statementis correct?

a. n = 1, since one mole of oxygen is being

considered.b. Addition of base should result in an E

value, which is less than 1.23 V.c. E is independent of the pH of the solution.d. Q = [H2O]

2

[O2] [H+]

33. The equilibrium constant for the gaseous

reaction C + D!" E + 2F is 3.0 at 50oC. In a

2.0 L flask at 50 oC are placed 1.0 mol of C, 1.0

mol of D, 1.0 mol of E, and 3.0 mol of F.Initially, the reaction willa. proceed at equal rates in both directions.b. proceed more rapidly to form E and F.c. proceed more rapidly to form C and D.

d. not occur in either direction.

Compound ∆Go

f kJ/mol

H2O(l) —237H2O(g) —229

34. At 298 K the equilibrium constant forH2(g) + ½ O2(g)!" H2O(l)

a. is larger than the Keq for

H2(g) + ½ O2(g)!" H2O(g)b. will have a value of 1 0 at equilibrium.c. cannot be computed since data on O2 and


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H2 are not provided.d. will have the same value as the K eq for

2 H2(g) + O2(g)!" 2 H2O(l)

35. Consider the reversible system atequilibrium:

2CO + O2 !" 2CO2 + heat

When the temperature is increased at constant pressure

a. the CO2 concentration will be increased.b. the CO2 concentration will be decreased.c. the amount of each substance will be

unchanged.

d. the amount of each substance will beincreased.

e. the result cannot be predicted from theinformation given.

36. The numerical value of the equilibriumconstant for any chemical change is affected by

changinga. the catalyst.b. the concentration of the products.

c. the concentration of reacting substances.d. the pressure.e. the temperature

37. What is the equilibrium constant expression

for the gas phase oxidation of CO to CO2 by O2?

a. K = [CO2]2

[CO][O2]

b. K= [CO]2 [O2][CO2]

c. K= [CO2]2

[CO]2 [O2]

d. K= [CO] [O2]

[CO2]

38. Into an empty vessel COCl2(g) isintroduced at 1.0 atm pressure whereupon itdissociates until equilibrium is established:

2COCl2(g)!" C(graphite) +CO2(g) + 2Cl2(g)

If x represents the partial pressure ofCO2(g) at equilibrium, what is the value ofthe equilibrium constant, Kp?

a. x.2x2 (1.0-2x)2

b. x x 2x2

(1.0-2x2)

c. x (2x)2

(1.0- 2x)2

d. x (2x)2 (1.0—x)2

39. At a certain temperature, the equilibriumconstant for the reaction 2HI(g)!"""" H2(g) +I2(g) is 0.49. Calculate the number of moles ofhydrogen produced when one mole of HI is

placed in a 1 L vessel at this temperature.a. 0.41b. 0.25

c. 0.29d. 3.45

40. What is the [OH-] of a solution which is

0.18 M in ammonium ion and 0.10 M in

ammonia? Kb = 1.8 x 10-5

a. 1.3x10-3 b. 1.0x10

-3

c. 1.3x10-5

d. 1.0x10-5

41. What is the pH of a 0.10 M solution of a

monoprotic acid, HA, with a Ka = 1.0 x 10-6

?a. 1.6b. 3.5

c. 5.0d. 6.0

42. When 0.10 mol of a weak acid HA wasdiluted to one liter, experiment showed the acid

to be 1% dissociated.HA + H2O!" H3O

+ + A-

What is the acid dissociation constant, Ka?a. 1 x10

-6

b. 1 x10-5

c. l x10-3 d. 1 x105

43. Which solution has a pH less than 7.0?a. 1 M NH4Cl

b. 1 M K 2CO3 c. 1 M NaOCld. 1 M NaOH

44. What is the pH of a 0.1 M NaF solution?Ionization constant for HF, Ka = 7 x 10

-4 a. 2.1b. 5.9c. 8.1d. 9.1


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45. What is the hydrogen ion concentration of a buffer solution containing 0.10 M NO2

1- and 0.20

M HNO2? Ionization constant for NitrousAcid, Ka = 4.5x 10

-4

a. 2.2x10-4Mb. 9.0 x 10

-4 M

c. 4.5 x 10-4

Md. 9.5 x 10-3M

46. The solubility of BaCO3 is 7.9 x 10-3 g/L.

Calculate the solubility product, K sp ignoringhydrolysis. MW of BaCO3 197 g/mol

a. 1.6x10-2 b. 1.6x10-9 c. 4.0x10

-5

d. 6.2x10-5

47. The addition of solid Na2SO4 to an aqueoussolution in equilibrium with solid BaSO4 will

cause

a. no change in [Ba2+] in solution.

b. more BaSO4 to dissolve.c. precipitation of more BaSO4.d. an increase in the K sp of BaSO4.

48. Assume that standardized aqueous solutions

of each of these are available.

Substance IonizationConstant

NaOAc Kb = 5.6 x 10-10

RNH3+Cl- Ka = 5.6 x 10-10

RNH2 Kb=1.8x10-5

HOAc Ka=1.8x10-5

A buffer with a desired pH is 5.0 would beconveniently prepared by appropriate mixtures of

a. NaOAc and HOAc

b. HOAc and waterc. NaOAc and RNH2

d. HOAc and RNH2

49. Which substance is most soluble in water?

a. C6H6 b. CaCO3 c. C2H5OHd. CO2

50. The solubility of BaCrO4 in water is 2.8 x10-3 g/L what is the K sp of the salt? MW of

BaCrO4 253 g/mola. 1.2x10

-10

b. 2.2x10-5 c. 2.8x10-3

d. 7.8 xl0-6

51. Which is the correct expression for the

solubility product constant for Ag2CrO4?a. K sp= [Ag+]

2 [CrO42-]

b. K sp= [2Ag+]2 [CrO4

2-]c. K sp= [Ag+] [CrO4

2-]d. K sp= [Ag+] [CrO4

2-]2 e. K sp= [2Ag+] [CrO4

2-]

52. The correct IUPAC name of N2O3 isa. nitrogen oxide.b. nitrogen(II) oxide.c. nitrous oxided. dinitrogen trioxide.

53. In which case is the substance with the

given formula followed by its correct name?a. KNO2 — potassium nitrateb. FeCl3 — iron(III) chloride

c. FeS — iron(II) sulfited. Mg3 N2 — magnesium nitritee. HClO — hydrochloric oxide

54. Balance the equation for the following

reaction, using no fractional coefficients.

? C +? HNO3"""" ? CO2 +? NO2 +? H2O

The sum of the coefficients in the balanced

equation isa. 5b. 7c. 9d. 12e. 16

55. Complete and balance the equation for the

reaction, where the reactants are in aqueoussolution. Use no fractional coefficients.

? Na3PO4 + ? Ba(NO3)2 " ? + ?

The number of moles and formula of the productcontaining Ba area. 3NaNO3 b. BaPO4c. Ba(PO4)2 d. Ba2P3 e. Ba3(PO4)2


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56. According to the kinetic molecular theory,

a. gaseous molecules are continuously inrandom motion and collisions are perfectly

elastic.b. the absolute temperature of a gas depends

on its molar mass.

c. the pressure exerted on a gas affects thespeed of its molecules.

d. gaseous molecules can travel in straight orcurved paths.

e. all gaseous molecules are diatomic.

57. The volume of a given mass of gas varies

inversely with pressure, provided that thetemperature remains constant because

a. attractive forces between gas molecules arenegligible.

b. attractive forces between gas molecules areappreciable.

c. the average kinetic energy of the moleculesof a gas is proportional to the absolutetemperature.

d. increasing the molecular concentration, atconstant temperature, means increasing the

number of collisions between moleculesand container.

e. collisions between gas molecules are

perfectly elastic.

58. The Kelvin temperature of one liter of gasis doubled and its pressure is tripled, volume willthen be

a.l/6 L

b.2/3 L

c.3/2 L

d. 6 L

59. Which gas, present in the same closedsystem, has the greatest average kinetic energy at

a given temperature?

a. Hydrogenb. neonc. carbon dioxided. None; the average kinetic energy is the

same for each gas.

60. A sample of neon occupies a volume of27.3 L at STP. What would be the neon volumeat 177 oC and 0.100 atm pressure?

a. 177 Lb. 350 Lc. 422 L

d. 450 L

61. Under the same conditions of temperatureand pressure, the gas whose molecules possessthe highest average speed isa. H2Ob. O2

c. F2 d. Ne

62. What is the volume of 2.00 mol of heliumgas at 27 oC and 3.00 atm?

a. 6.1x10-2Lb. 1.48Lc. 16.4Ld. 44.8 L

63. Real gases are most like ideal gases at

a. high pressure and high temperature.b. low pressure and low temperature.

c. high pressure and low temperature.d. low pressure and high temperature.

64. 500 mL of a gaseous compound has a massof 0.9825 g at 0oC and 760 mmHg. What is the

approximate molar mass of the compound?a. 19.7b. 38.7c. 44.0d. 58.9

65. The partial pressures of a gaseous mixture

are given in the table. What is the mole percentof hydrogen?

Partial Pressures

hydrogen 200 mmHg

carbon dioxide 150 mmHg

methane 320 mmHg

ethylene 105 mmHg

a. 20.0b. 25.8

c. 38.8d. 41.7


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66. It is desired to collect enough oxygen overwater at 25

oC and 750 mmHg barometric

pressure to be equivalent to 1 L of pure oxygen at0 oC and 760 mmHg. The vapor pressure of water

at 25 oC is 23.5 mm. The volume collected isa. 1 L (298/273)(750/760)b. 1 L (273/298)((750-23.5)/(760-23.5))

c. 1 L (273/298)((750-23.5)/760)d. 1 L (298/273)(760/(750-23.5))

67. Methane, CH4, diffuses in a given apparatusat the rate of 30 mL/min. At what rate would agas with a molar mass of 100 diffuse under thesame conditions? MW of CH4 = 16 g/mol

a. 0.77 mL/min

b. 30 mL/minc. 6.7 mL/min

d. 75 mL/mine. 12.0 mL/min

68. The Arrhenius equation, k= Ae-E/RT

expresses the relationship between the reactionrate constant, k, and the energy of activation, E.The probability that colliding molecules will

reacta. increases with increasing energy of

activation.b. depends only on the empirical constant, A.c. increases with decreasing temperature.

d. decreases with increasing energy ofactivation.

69. The rate law for the reaction A+B"C+D isfirst order in [A] and second order in [B]. If [A]

is halved and [B] is doubled, the rate of thereaction will

a. remain the sameb. be increased by a factor of 2.c. be increased by a factor of 4.d. be increased by a factor of 8.

70. The addition of a catalyst in a chemical

reactiona. increases the concentration of products at

equilibrium.b. increases the fraction of reactant molecules

with a given kinetic energy.c. provides an alternate path with a different

activation energy.d. lowers the enthalpy change in the overall

reaction.

71. The following mechanism has been proposed for the formation of ethylbenzene:

CH3CH2Br + AlBr 3 " AlBr 4- + CH3CH2

+

CH3CH2+

+ C6H6" C6H6CH2CH3+

C6H6CH2CH3+

+ AlBr 4- "AlBr 3 + HBr +

C6H5CH2CH3

Which substance serves as the catalyst?

a. AlBr 3b. CH3CH2

+ c. AlBr 4

- d. C6H6CH2CH3

+

72. Which substance has the highest boiling

point?

a. CH4

b. Hec. HFd. Cl2

73. The table presents data for the reaction: The

temperature of the reaction is constant. The initialrate is in arbitrary units.

2H2(g) + 2NO(g)" 2H2O(g) + N2(g)

Initial Concentration (mol/L)

Exp. [NO] x 10-3 [H2] x 10-3 Initial Rate

I 6.0 1.0 18

II 6.0 2.0 36III 1.0 6.0 3

IV 2.0 6.0 12

What is the rate law for this reaction?a. rate = k 1 [H2][NO]b. rate = k 1 [H2]

2 [NO]2

c. rate = k 1 [H2]2 [NO]

d. rate = k 1 [H2] [NO]2

74. The reaction 2A + 2B"""" C +D proceeds bythis mechanism:

2A!" A2 (equilibrium)

A2 + B"""" X + C (rate determining)X+B"D (rapid)The rate equation for the reaction is

a. rate = k[A] [B]b. rate = k[A]

2[B]

2/[C][D]

c. rate = k[A]2[B]

2[D]

d. rate = k[A]2 [B]


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75. What is the correctly reported mass ofwater based on this data?

Mass of beaker and water 29.62 g

Mass of beaker only 28.3220 g

a. 1.3g

b. 1.30gc. 1.298g

d. 1.2980g

76. When a small single piece of magnesium

ribbon is dropped into a test tube half filled withdilute sulfuric acid, the metal soon floats to the

surface of the liquid. The best explanation forthis is that, (Densities, Mg, 1.79 g/cm3;

H2SO4(dilute) 1.2 g/cm3)

a. the metal is less dense than the acid.

b. the metal gets hot and expands anddecreases its density markedly as it reacts

with the acidc. the magnesium sulfate formed increases the

density of the solution.

d. gas bubbles attached to the metal buoy themetal to the top.

e. convection currents set up in the acid carrythe metal to the top.

77. The equilibrium vapor pressure of a fewliters of a liquid is dependent on

a. the mass of the liquid.b. the surface area of the liquid

c. the temperature onlyd. the volume of the liquid

78. The edge of a unit cube of an element Y,containing two atoms per unit cube, was found(by X- ray diffraction) to be 3.16 x 10-8 cm. Thedensity of the metal is 19.35 g/cm3. What is the

approximate atomic molar mass of Y?

a. 65.4b. 92.0c. 184d. 238

79. When a hypothetical ionic crystal M+X- is

heated, it vaporizes to form separate M+(g) andX-(g) ions. The energy required for this

vaporization (the lattice energy) will be greatestwhen

a. the electron affinity of X is small inmagnitude and the ionization potential of Mis large in magnitude.

b. the heat of vaporization of crystalline M issmall.

c. the heat of vaporization of crystalline M is

large.d. the effective radii of M+ and X- are large.

e. the effective radii of M+ and X- are small.

80. The stronger the intermolecular forces in asubstance

a. the higher the boiling point.b. the lower the boiling point.c. the higher the vapor pressure.d. the smaller the deviation from ideal gas

behavior.

81. Which group of substances is correctlyarranged in order from the highest to the lowestmelting point?

a. HF>H2>NaFb. NaF>H2>HFc. HF>NaF>H2 d. NaF>HF>H2

82. The fact that H2O has a dipole moment

suggests that the water molecule is

a. dimeric

b. symmetrical.c. bent.d. nonpolar.

83. Which pair is geometrically similar?

a. SO2 and CO2 b. CO2 and OF2 c. PH3 and BF3

d. SO2 and O3

84. The bond type and molecular polarity of

SiCl4 are

Bond Type Polarity of Moleculea. polar nonpolarb. polar polarc. nonpolar polard. nonpolar nonpolar


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85. The fact that BCl3 is a planar moleculewhile NCl3 is pyramidal can be explained severaldifferent ways. Which is the best rationalization?

a. Nitrogen is more electronegative than boron.

b. The nitrogen atom in NCl3 has a lone pair

of electrons whereas the boron atom inBCl3 does not.

c. The nitrogen atom is smaller than the boronatom

d. The boron atom in BCl3 is sp3 hybridized,

while the nitrogen atom in NCl3 is sp2

hybridizes

86. The geometry for SeF3+ is

a. trigonal pyramidal.b. tetrahedral.c. square planar.

d. rectangular planar.

87. The Lewis structure of BrF5 isF

F F

BrF F

The molecular structure of BrF5 is

a. square pyramidal.b. trigonal pyramidal.

c. trigonal bipyramidal.d. octahedral.

88. Which is planar?

a. PCl3b. ClO3

-

c. CO32-

d. NH3e. PH3

89. A molecule of the type ML4 consists of four

bonding pairs of electrons and no lone pairs.Which structure would it be expected to assume?a. square planarb. tetrahedralc. lineard. square pyramidal

90. A sample of a radioactive isotope initially

contains 20 x 1010 atoms. After 16 days, 5 x 1010 atoms remain. What is the half-life of the

isotope?

a. 4 daysb. 8 days

c. 12 daysd. 16 days

91. Which of these molecules is the most polar? (X and Y are two different elements, Y

being the more electronegative.)

a. X2 b. Y2 c. X—Y—X

d. X—YX

Xe. Y—X

X

92. In the beta emission of a species such as14

6C the process may be considered as

a. the change of a proton into a neutron.

b. the change of a neutron into a proton.c. the same mode of decay as electron capture.d. neutrino absorption by the nucleus.

93. Which compound is a paraffin (methaneseries) hydrocarbon?

a. C5H12 b. C5H11OH

c. (C2H5)2Od. C6H6 e. C6H5Cl

94. lsobutane differs from butane in that theformer

a. has a higher molecular weight.b. has a different percentage composition.

c. is not a saturated hydrocarbon.d. has a different empirical formula.e. has a different structural formula.

95. Which has the highest boiling point?

a. n-butane C4H10 b. n-heptane C7H16 c. n-hexane C6H14 d. n-pentane C5H12


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96. The reaction between acetic acid and ethylalcohol is classified as

CH3COOH + C2H5OH"""" CH3COOC2H5 + H2O

a. saponificationb. addition

c. esterificationd. hydrolysis

97. Manganese has the oxidation number of +5in

a. [MnF6]3-

b. Mn2O7 c. [MnO4]

2- d. [Mn(CN)6]

1-

98. The highest oxidation number of vanadiumis exhibited in

a. VO2+

b. VBr 4

c. NH4VO3 d. V2(SO4)3 e. V(CN)6

3—

99. Fe(s) + Cu2+ (aq)"""" Cu(s) + Fe

2+ (aq)

Which statement is true for the reaction?

a. Cu2+

is oxidized.b. Cu

2+gains in oxidation state.

c. Cu2+ is reduced.

d. Fe(s) is reduced.

100. Which is the strongest oxidizing agent?

Standard Potentials E o

Na" Na+ + e 2.71 V

Cd" Cd2+

+ 2e 0.40 V

H2 " 2H+ + 2e 0.00 V

Ag"Ag+ + e -0.80 V

a. Na+ b. H2

c. Cd0 d. Ag+

101. In this reaction

3Mg + 2HNO3(dilute) + 6H" 3Mg2+ + 2NO + 4H2O

the magnesium acts as a reducing agent. Howmany electrons does each magnesium atomlose?

a. 1b. 2c. 3

d. 4e. 6

102. Which of these isoelectronic ions is themost polarizable?

a. Na+

b. O2- c. F- d. Mg

2+

103. The greatest oxidizing power (tendency togain electrons) is shown by


Na" Na+ + e 2.714 V

Al" Al3++3e 1.67 V

Sn2+"Sn4++2e -0.14 V

21 — " l2+2e -0.535 V

2F — "F2 + 2e -2.85 V

a. Na+ b. Alc. Sn

4+

d. F2

104. Which metal will reduce copper(ll) ions butnot zinc ions?


Na" Na+ +e 2.71 V

Zn" Zn2+

+2e 0.76 V

Fe" Fe2+ + 2e 0.4 V

Pb" Pb2++2e 0.13 V

H2 " 2H++ 2e 0.00 V

Cu" Cu2++2e -0.34.V

Hg" Hg2++2e -0.85 V

Ag" Ag+ +e -0.80 V

a. Nab. Hgc. Pb

d. Ag


11/18


105. A metal, M, forms an oxide of formulaM2O3. The ground state valence shell electronconfiguration of the M atom is

a. ns2np1 b. np6 c. 4s

13d

10

d. 4f 7

106. From your knowledge of the periodicnature of the elements, what formula would beanticipated for gallium selenide?

a. GaSe

b. GaSe2 c. Ga2Sed. Ga2Se3

107. Use this section of a periodic table.

A EQ R

If atoms of R have one “d” type electron, whatis the formula for a nitride of element A?

a. A3 Nb. A3 N2c. AN

d. AN2

108. In which pair of particles is the first

member larger than the second member?

a. Li+ ; Be2+ b. Li+ ; Na+c. Li+ ; Lid. Be ; Mg

109. Which would be expected to be the mostelectronegative?

a. Pb. As

c. Si

d. Al

110. Predict which element would have thelargest difference between its first and second

ionization energies.a. Sodiumb. Phosphorusc. Silicond. magnesium

111. In which reaction is the energy termreferred to as the ionization energy?

a. NaCl(crystal) + energy"""" Na+(g) + Cl

— (g)

b. Cl(g) + energy"Cl+ + ec. Cl(g) + e"""" Cl

— (g) + energyd. Cl

— g) + H

+(g)"""" HCl(g) + energy

112. Based on their positions in the periodic

table, which is most likely to replace selenium,Se, in a biological system?a. Teb. Brc. As

d. I

113. Which conditions favor the high solubilityof a gas in a liquid?a. high pressure, high temperature

b. high pressure, low temperaturec. low pressure, high temperatured. low pressure, low temperature

114. Ionic compounds in the solid state at room

temperature are generally characterized by theira. ability to conduct an electric current.b. high vapor pressures.c. solubility in polar solvents.d. solubility in nonpolar solvents.

e. low melting points.

115. Which precipitate will not dissolve inaqueous HCl solution?a. AgBrb. BaCO3c. CaSO3 d. Fe(OH)3 e. ZnS

116. A cellophane bag, which acts as amembrane permeable only to water, contains a 2

M sugar solution. The bag is immersed in a 1 Msugar solution. What will happen?

a. The bag will soon contain more solutionthat will be are concentrated than 2 M.

b. The bag will soon contain more solutionthat will be less concentrated than 2 M.

c. The bag will lose sugar and the solution init will become less concentrated.

d. The bag will lose water and the solution in

it will become more concentrated.e. There will be no change.


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117. If 0.400 g of a substance R (MW = 80.0g/mol) is dissolved in 100 g of liquid Q, what isthe molality of the solution?

a. 4.00x10 –3 mb. 5.00x10 –2 mc. 5.00 x 10

–3m

d. 4.00 x 10 –1

m

118. What is the mole fraction of water in 200. gof 95% (by mass) ethanol, C2H5OH (mw = 46.0g/mol)?

a. 0.050

b. 0.12c. 0.56d. 0.88

119. A 0.10 m aqueous solution of HF shows a

freezing point of - 0.198o

C. What is the percentdissociation of HF? Molal freezing point

constant, K f for water = 1 .86oC/m

a. 6.4%

b. 10%c. 20%d. 98%

120. A 0.10 m solution of MgSO4 freezes

at -0.245oC instead of 2 x (- 0.186 oC) as predicted for ideal behavior. This deviation from

ideality can best be explained on the basis of

a. interionic attraction.

b. hydrogen bonding.c. the Le Chatelier principle.d. the solubility product constant

121. Which aqueous solution has the smallestfreezing point depression?

a. 0.2 m Ca(NO3)2 b. 0.2 m MgSO4

c. 0.2 m CH3OHd. 0.2 m K 3PO4

122. When one mole of naphthalene is dissolvedin 1000 g of benzene, the freezing point changesfrom 5.51 oC to 0.41

oC. When 20 g of anunknown organic compound is dissolved in 500 gof benzene, the freezing point of this solution is

5.00 oC. What is the molar mass of the unknownorganic compound?

a. 40 g./molb. 200 g/molc. 100 g./mol

d. 400 g/mole. 128 g./mol

123. When dilute aqueous solutions of lead(II)nitrate and potassium bromide are mixed, a

precipitate is observed. The products of thisreaction are

a. Pb2+(aq) + Br

1- (aq) + KNO3(s)b. Br 2(aq) + NO2(g) + PbK 2(s)

c. PbO(s) + K +(aq) + Br 1-(aq) + NO2(g)d. PbBr 2(s) + K

+(aq) + NO31-(aq)

124. Assuming ideal behavior, what is the vapor pressure of a solution of 16.0 mol of carbon

tetrachloride and 4.00 mol of dioxane at 23o

C?

Vapor Pressure @ 23 oC

Carbon tetrachloride 100. mm Hg

Dioxane 38.00 mm Hg

a. 50.4 mmHgb. 62.8 mmHgc. 74.2 mmHgd. 87.6 mmHg

125. What is the empirical formula for the

substance with this analysis: Na=54.0%,B=8.50%, O=37.5%

a. Na3BO3 b. Na4BO4 c. Na2B2O3 d. NaB2O2

126. A hydrocarbon undergoes completecombustion to give 0.44g of CO2 and 0.27 g ofH2O. What is the simplest (empirical) formula of

the hydrocarbon?

a. C44H27 b. CH4 c. C2H3 d. CH3


13/18


127. A 6.80 g coin was dissolved in nitric acidand 6.21 g of AgCl was precipitated by theaddition of excess sodium chloride, Calculate the

percentage silver in the coin.

Ag +(aq) + Cl 1-(aq)" AgCl(s)a. 24.7%b. 68.7%

c. 75.3%d. 91.3%

128. A 40- mL portion of a 0.1 M MgSO4 solution contains how many grams of MgSO4?a. 120 gb. 24 g

c. 0.96 gd. 0.6 ge. 0.48 g

129. An aqueous solution containing 49 g of

sulfuric acid per liter has a concentration ofa. 0.50 Mb. 1.0Mc. 4.9% by massd. 4.9M

130. One hundred milliliters of a solution of

oxalic acid, (COOH)2, is neutralized with 50.0mL of 0.750 M KOH solution. What is themolarity of the oxalic acid solution?

a. 0.099 Mb. 0.375 M

c. 0.188 Md. 0.750 Me. 0.333 M

131. How many L of CO2 gas at STP can be

obtained by burning one mole of C3H8?C3H8(g) + 5 O2(g)"3 CO2(g) + 4H2O(g)a. 11.2b. 44.8c. 67.2d. 112

132. What volume of ammonia gas, NH3,measured at STP, will be produced by thedecomposition of two moles of ammonium

carbonate?(NH4)2CO3(s)"""" 2NH3(g) + CO2(g) + H2O(g)a. 22.4 Lb. 33.6 Lc. 44.8 Ld. 89.6 Le. 112 L

133. Which change is likely to be accompanied by the greatest increase in entropy?

a. N2(g) + 3H2(g)"""" 2NH3(g) (at 25oC)

b. Ag+(aq) + Cl1-(aq)"""" AgCl(s) (at 25oC)

c. CO2(s)"""" CO2(g) (at - 70oC)

d. H2O(g)"""" H2O(l) (at 100oC)

134. When 45.0 g of an alloy at 100.0oC is

dropped into 100.0 g of water at 25.0 oC the finaltemperature is 37.0 oC. What is the specific heatof the alloy? (for water, specific heat = 4.184 J g-1 oC-1)a. 0.423 J g-1 oC-1

b. 1.77 J g-1 oC-1 c. 9.88 J g-1 oC-1 d. 48.8 J g

-1 oC

-1

135. What is the standard enthalpy of

combustion of C2H6 in kJ mol-1

?

Reaction ∆∆∆∆Ho

H2(g) + ½ O2(g) " H2O(l) -286 kJ

C2H4(g) + H2(g) " C2H6(g) -137 kJC2H4(g) + 3 O2(g)" 2 CO2(g) + 2

H2O(g) -1412 kJ

a. –1275 kJb. –31561 kJc. –1558 kJd. +1834 kJ

136. Given these equationsSO2(g)" O2(g) + S(s) ∆H

o = +300 kJ

2SO2(g) + O2(g)"""" 2SO3(g) ∆Ho = - 200 kJ

calculate the heat of formation of SO3(g).a. –500 kJ.mol-1 b. +100 kJ.mol-1 c. –400 kJ.mol-1 d. +200 kJ.mol

-1

137. More heat is derived from cooling onegram of steam at 100 oC to water at 50 oC than

from cooling one gram of liquid water at 100o

C to 50

oC because

a. water is a poor thermal conductor.

b. the steam is hotter than the water.c. the steam occupies a greater volume than

the water.d. the density of water is greater than that of

steam.

e. the heat of condensation is evolved.


14/18


138. Calculate the value of (in kJmol-1) for thereaction

N2(g) + 3H2(g)"2NH3(g)

Bond Energies (kJ. mol-1)

H—H 435

N=N 946 (in N2) N—H 389

a. 2340 kJ of heat absorbedb. 213 kJ of heat absorbed

c. 2340 kJ of heat evolvedd. 83 kJ of heat evolved

139. When Al2O3(s) is formed from the elements

at standard conditions, the values of ∆Η o and ∆G

o at 298 K are -1617 kJ.mol-1 and -1577 kJ.mol-1,

respectively. The standard entropy of formation per mole, in joules per degree, will bea. -315b. -134c. - 93.3d. 0.0933e. +15.7

140. Vaporization of a liquid is an example of a process for which

a. ∆H, ∆S, and ∆G are positive at alltemperatures.

b. ∆H and ∆S are positive.c. ∆G is negative at low temperatures,

positive at high temperatures.

d. ∆H=∆S

141. Consider the boiling point of a series ofhydrogen compounds. The abnormally high

boiling point for water is due to

BP

H2O H2S H2Se H2Te

a. extensive hydrogen bonding

b. its low dipole moment.c. the extreme stability of the compound.d. the high electronegativity of hydrogen.

142. Which nuclear equation is properly balanced?a.

4He + 9Be " 12C + 1Hb.

4He + 14 N " 17O + 1H

c.4He + 24Mg " 27Si + 1H

d.14 N + 0-1e "

14O

143. What is the correct reading for the buret?32

33

a. 32 mLb. 32.2 mLc. 32.26 mLd. 33.74 mL

144. A particular chemical reaction has a

negative ∆H and negative ∆S. Which statement iscorrect?

a. The reaction is spontaneous at alltemperatures.

b. The reaction is nonspontaneous at all

temperatures.c. The reaction becomes spontaneous as

temperature increases.d. The reaction becomes spontaneous as

temperature decreases.

145. Which line in the diagram represents theactivation energy for a forward reaction?

a. A A Db. B Ec. Cd. D B C

Reaction Coordinate

H

146. The group —C=O is characteristic ofa. aldehydes.b. ketones.c. alcohols

d. esterse. acids


15/18


147. Uranium—234 undergoes spontaneousradioactive decay to give an alpha particle and anew nucleus, X.

234U " 4He + X What is X?a.

23090U

b.230

90Th

c.238

94Ud.

23894Pu

148. Which is classified as an alkene?O

a. CH3 —CH2 —C—H

b. CH3CH2CH3 c. CH3 —C = C H

d. CH2 HC CH2

HC CH2CH2

149. An example of an organic acid is

O

a. CH3CH2COCH3 O

b. CH3CH2COHO

c. CH3CH2CNH2 O

d. CH3 CH2CH

150. Consider the phase diagram of a purecompound. Which statement applies?

A CP

B

Temperature

a. The path A" C represents sublimation.b. Following the path A"""" B""""C the

compound would first liquefy and thenvaporize.

c. If the compound is in state A, continued

reduction of the pressure (at constanttemperature) will cause it to melt.

d. None of these statements is correct.

151. Which is the formula of an alcohol?

a. CH3CH2CH2 —O—CH3 b. CH3CH2CH2CH2 – O H

O

c. CH3 CH2 —C—CH3 O

d. CH3CH2CH2C—H

152. Which choice best indicates the degree of correctness of this statement? “The boiling point of normal propanol is lower than the boiling point of turpentine.”

Vapor Pressure of Substances in mmHg

Temperature 0oC 20oC 50oC 80oC 95oC 100oC

n-propanol 3.4 14.5 87.2 376 697 836Water 4.6 17.6 92.0 354.9 760

Turpentine 2.1 4.4 17.0 61.3 131.1

a. The statement is true.b. The statement is probably true; additional data would be needed for a final decision.c. It is impossible to judge the statement because the data are insufficient.d. The statement is probably false; additional data would be needed for a final decision.

e. The statement is false.


16/18


V a p o r p r e s s u r e m m H

g

153. For the reaction 2H2O2"2H2O +O2 Which plot confirms that the rate is first order with respect to

H2O2?

a. b. c. d.

[H2O2] 1/[H2O2] [H2O2]2 log[H2O2]

time time time time

154. Sulfur dioxide can be described by the structures:

S S

O O O OThis implies that

a. the two bonds in SO2 are of equal length, and the electronic distribution in the two SO bonds isidentical.

b. the single bond is longer than the double bond and the electronic distribution in the two SO bonds isdifferent.

c. an electron pair in the SO2 molecule alternates back and forth between the two sulfur— oxygen electron pairs so that the two different bonds seem to exchange positions.

d. the SO2 molecule revolves so that the two different bonds seem to exchange positions.

155. The graph shows how the vapor pressure of liquid A and of liquid B changes with the temperature.

Select the choice that best indicates the degree of correctness of this statement: “The normal boiling point ofliquid B is 78

0C.”

1000

900800

A

600B

400300200100

0 20 40 60 80 100 120

Temperature oC

a. The statement is true.b. The statement is probably true; additional data would be needed for a final decision.c. It is impossible to judge the statement because data are insufficient.d. The statement is probably false; additional data would be needed for a final decision.e. The statement is false.


17/18


156. The isomerism represented byH H H H H H

H— C—C—C—O—H and H—C—C—O—C—H

H H H H H H

a. cis—trans. b. optical.

c. positional.d. geometric.

157. In a sample of a nearly ideal gas, this graph could represent a plot of

a. V vs. T at a given constant P. b. P vs. T at a given constant V. c. P vs. V at a given constant T d. PV vs. P at a given constant T

158. A mixture of 100 g of K 2Cr 2O7 and 200 g of water is stirred at 60o

C until no more of this salt dissolves.The resulting solution is decanted (poured off) and cooled to 20 oC. What mass of K 2Cr 2O7 crystallizes from

the solution during the cooling?

80

60Solubility(g/100 mL)

40

20

0 20 40 60 80 100Temperature in oC

a. 24 gb. 31 gc. 43 gd. 58 ge. 86 g

159. The height of the mercury in the right arm open to atmospheric pressure (760 mmHg) is 100 mm and

the height in the left arm is 120 mm.

gas

What is the pressure of the gas in the bulb?

a. 20 mmHgb. 640 mmHg 120 mmc. 740 mmHg 100 mmd. 780 mmHg


18/18


Key to Answers

Q # Ans Q # Ans Q# Ans Q# Ans Q# Ans

1 D 36 E 71 A 106 D 141 A

2 B 37 C 72 C 107 B 142 B

3 A 38 C 73 D 108 A 143 C

4 A 39 C 74 D 109 A 144 D5 D 40 D 75 B 110 A 145 A

6 D 41 B 76 D 111 B 146 A

7 A 42 B 77 C 112 A 147 B

8 A 43 A 78 C 113 B 148 D

9 D 44 C 79 E 114 C 149 B

10 A 45 B 80 A 115 A 150 D

11 D 46 B 81 D 116 B 151 B

12 D 47 C 82 C 117 B 152 A

13 C 48 A 83 D 118 B 153 D

14 D 49 C 84 A 119 A 154 A

15 D 50 A 85 B 120 A 155 A16 A 51 A 86 A 121 C 156 C

17 C 52 D 87 A 122 D 157 C

18 C 53 B 88 C 123 D 158 D

19 A 54 D 89 B 124 D 159 C

20 A 55 E 90 B 125 A

21 B 56 A 91 D 126 D

22 C 57 D 92 B 127 B

23 D 58 B 93 A 128 E

24 C 59 D 94 E 129 A

25 A 60 D 95 B 130 C

26 A 61 A 96 C 131 C

27 A 62 C 97 D 132 D28 B 63 D 98 C 133 C

29 D 64 C 99 C 134 B

30 C 65 B 100 D 135 C

31 A 66 D 101 B 136 C

32 B 67 E 102 B 137 E

33 C 68 D 103 D 138 D

34 A 69 B 104 C 139 B

35 B 70 C 105 A 140 B

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