Practice Exam

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1. Which of the following is an example of chemical change?
a. water boiling / b. ice melting / c. natural gas burning
d. alcohol evaporating / e. iodine vaporizing
2. Which of the following equations is not balanced?
1. ZnCl2 + NaOH -> Zn(OH)2 + NaCl
2. Fe2O3 + 2CO -> 2Fe + 2CO2
3. NH4NO3 -> N2O + 2H2O
a. 1. / b. 2. / c. 3. / d. 1 and 2. / e. all of them.
3. How many molecules are in 1.00 kg of hydrazine, N2H4?
a. 9.40 x 1021 / b. 1.88 x 1022 / c. 1.13 x 1023 / d. 1.88 x 1025 / e. 1.13 x 1026
4. An oxide of phosphorus is 43.7% P, 56.3% O b y mass, and has a molecular weight of 284 g. What is its molecular formula?
a. P2O5 / b. P2O3 / c. P4O10 / d. P2O6 / e. P4O6
5. The titration of HCl with NaOH is represented by the equation
HCl + NaOH -> NaCl + H2O
What volume of 0.100M HCl is required to titrate 50.0 ml of 0.500 M NaOH?
a. 50.0 mL / b. 100 mL / c. 200 mL / d. 250 mL / e. 500 mL
6. A balloon contains 1.0 L of gas at sea level, where the pressure is 1.0 atm. What will the volume be when the pressure is 0.80 atm, the temperature remaining constant?
a. 1.3 L / b. 0.80 L / c. 0.20 L / d. 1.0 L / e. 1.8 L
7. A 1.00 g sample of KC1O3 decomposes to yield oxygen, which is collected at 25.0OC and 735 mmHg. What volume of oxygen is collected?
2KC1O3(s) -> 2KCl(s) + 3O2(g)
a. 227 mL / b. 309 mL / c. 208 mL / d. 155 mL / e. 465 mL
8. The atmosphere of the imaginary planet Gorp has the following partial pressures of its component gases: 427.7 mmHg O2, 336.0 mmHg N2, 38.1 mmHg CO2, and 510.2 mmHg Ne. What is the mole fraction of oxygen in the Gorpian atmosphere?
a. 1.000 / b. 0.00234 / c. 0.307 / d. 0.326 / e. 0.563
9. Which of the following statements is false?
a. The reaction vessel cools when an endothermic reaction occurs.
b. An exothermic reaction is characterized by a negative value of DH.
c. Heat is evolved when an exothermic reaction occurs.
d. Heat is added to the system in an endothermic reaction.
e. An endothermic reaction causes the surroundings to absorb heat.
10. What is the quantity of heat evolved when 100.0 g of H2O(l) are formed from the combustion of H2(g) and O2(g) via the reaction: H2(g) + 1/2 O2(g) -> H2O(l) DHo = -285.8 kJ
a. 285.8 kJ / b. 2.858 x l04 kJ / c. 51.44 kJ / d. 2297 kJ / e. 1587 kJ
11. Calculate the standard enthalpy change, D Ho, for the combustion of C3H6(g)
C3H6(g) + 9/2 O2(g) -> 3CO2(g) + 3H2O(l)
D Hf o values in kJ/mol are as follows: C3H6(g) = 21; CO2(g) = -394; H2O(l) = -286.
a. -2061 kJ / b. -2019 kJ / c. -701 kJ / d. 2019 kJ / e. 2061 kJ
12. Using the following data, calculate the heat of reaction for the coal gasification process
2C(s) + 2H2O(g) -> CH4(g) + CO2(g)
C(s) + H2O(g) -> CO(g) + H2(g) DHo = +131.3 kJ
CO(g) + H2O(g) -> CO2(g) + H2(g) DHo = -41.2 kJ
CO(g) + 3H2(g) -> CH4(g) + H2O(g) DHo = -206.1 kJ
a. 15.3 kJ / b. 378.6 kJ / c. -116.0 kJ / d. -378.6 kJ / e. -157.2 kJ
13. How many protons, electrons, and neutrons are in one atom of Sn-119?
a. 119p, 50n, 119e / b. 50p, 69n, 50e / c. 50p, 69n, 119e
d. 69p, 50n, 69p / e. 50p, 119n, 169p
14. What is the energy of a photon of ultraviolet radiation, l = 5.00 x 10-8 m?
a. 1.11 x 10-49 J / b. 1.67 x 10-16 J / c. 9.95 x 10-33 J
d. 3.98 x 10-18 J / e. 7.24 x l0-12 J
15. The square of the wave function, y 2, of an electron in an atom
a. describes the energy of the electron. / b. specifies the momentum of the electron.
c. gives the probability of finding the electron in a region of space.
d. is proportional to the velocity of the electron.
e. is inversely proportional to the distance between the electron and the nucleus.
16. Which of the following statements is or are true?
1. An excited atom can return to a lower energy level by absorbing light energy.
2. An atom can be excited by emitting light energy.
3. As the energy of electromagnetic radiation increases, its frequency increases.
a. 1 / b. 3 / c. 2 and 3 / d. 1 and 3 / e. 3 and 4
17. What is the maximum number of electrons in any principal quantum level, n?
a. 2n2 / b. n2 + 4 / c. 2n + 4 / d. 2(2n+4) / e. 2(n2+1)
18. Which type of orbital is not allowed?
a. ls / b. 5f / c. 4p / d. 2d / e. 5s
19. Which ground-state electronic configuration is incorrect?
a. Cr: [Ar] 3d6 / b. Ca: [Ar] 4s2 / c. Na: 1s22s22p63s1
d. Zn: [Ar] 3d104s2 / e. Kr: [Ar] 3d104s24p6
20. Which of the following has the largest atomic radius?
a. Ba / b. Ca / c. As / d. At / e. Ar
21. Which of the following elements do you expect Zn to resemble most closely in its properties?
a. Ca / b. Ga / c. Sc / d. Cd / e. Ni
22. What is the formula of aluminum nitrate?
a. AlNO3 / b. A13NO3 / c. A12(NO3)3 / d. Al(NO3)2 / e. Al(NO3)3
23. The molecular geometry of the SO3 molecule is best described as
a. linear / b. trigonal planar / c. tetrahedral / d. bent / e. trigonal pyramidal
24. What hybrid orbitals of sulfur are involved in the bonding in gaseous SO3?
a. sp / b. sp2 / c. sp3 / d. dsp2 / e. d2sp3
25. Which of the following is a weak base?
a. NH3 / b. HCl / c. KOH / d. NaOH / e. Ba(OH)2
26. All of the following compounds are soluble in water except.
a. NaCl / b. ZnCl2 / c. AgNO3 / d. KI / e. FePO4
27. What is the oxidation number of P in H3PO2?
a. -3 / b. 0 / c. +1 / d. +3 / e. +7
28. Which of the following compounds is expected to have the highest vapor pressure?
a. CH3CH2CH3 / b. CH3CH2NH2 / c. CH3CH2OH / d. CH3CH2CH2CH3 / e. CH3CH2CH2Cl
29. Let us assume that solid copper metal has a cubic unit cell. The edge of the cubic unit cell is
4.5 x 10-8 cm. Which of the following unit cells would give a material with the highest density?
a. a simple cubic cell / b. a body-centered cubic cell / c. a face-centered cubic cell
d. The density would be identical for all of these cells if the edge of each cell is the same.
e. Not enough information to determine.
30. Which of the following noble gas elements has the highest boiling pt.?
a. Ne / b. He / c. Xe / d. Kr / e. Ar
31. Which of the following gases can be liquefied at 25oC.
a. only CH3Cl (critical pt. 144oC, 66 atm) / b. only SO2 (critical pt. 158oC, 78 atm)
c. only CH4 (critical pt. -82oC, 46 atm) / d. both a and b.
e. none of the above.
32. Which of the following solutes dissolved in 1.0 kg of water would be expected to cause the water to freeze at the lowest temperature?
a. 0.0015 moles of glucose, C6Hl2O6 / b. 0.0015 moles of HF
c. 0.0020 moles of methanol, CH3OH / d. 0.0015 moles of H2SO3
e. 0.0015 moles of AgNO3
33. Which of the following as a solid has a crystal structure containing discrete or separate molecules?
a. NaCl / b. CH4 / c. C (graphite) / d. C (diamond) / e. BN
34. Which of the following compounds would be expected to have the highest crystal lattice energy?
a. LiF / b. LiI / c. CsI / d. CsF / e. NaCl
35. How much energy is required to change 40.0 g of water at 25oC and 1 atm to steam at 100o C?
DHvap = 2257 J/g; specific heat H2O(l ) = 4.18 J/(g oC).
a. 12.5 kJ / b .77.8 kJ / c. 51.4 kJ / d. 103 kJ / e. 90.3 kJ
36. Which of the following molecules is polar?
a. CH4 / b. CC14 / c. CO2 / d. NO2 / e. SF6
37. When 1 mol of O2 is consumed in the reaction 3Fe + 2O2 -> Fe3O4, how much Fe3O4 is produced?
a. 1.0 mol / b. 0.50 mol / c. 5.0 mol / d. 2.0 mol / e. 1.5 mol
38. For the elementary step A + 2B k1-> C + D, the rate law is given as:
a. rate = k1[A][B] / b. rate = k1[A][B]2 / c. rate = k1[A][B]2 - k1[C][D]
d. rate = k1[A][B]1/2 / e. none of these
39. The rate of a first order reaction, rate = k[A], can generally be increased by:
a. lowering the temperature of the reaction. / b. raising the temperature of the reaction.
c. employing a catalyst. / d. decreasing the concentration of A. / e. b and c
40. A Bronsted-Lowry acid is one that
a. makes OH- in an aqueous solution / b. is a proton donor / c. is an electron donor
d. is a proton acceptor / e. gives off a color when the pH is below 7.
41. The numerical value of the equilibrium constant, Kc, for a particular rxn., is, in general, a function of:
a. the pressure / b. the temperature / c. the amount of products
d. the presence of a catalyst / e. all of these
42. Which of the following reactions will be nearly complete in the forward direction at equilibrium?
a. 2NO(g) + 2H2(g) -<- N2(g) + 2H2O(g) Kc = 6.5 x 1073
b. CO2(g) + C(s) -<- 2CO(g) Kc = 0.11 x 101
c. N2(g) + O2 (g) -<- 2NO Kc = 4.6 x 10-31
d. COCl2(g) -<- CO(g) + Cl2(g) Kc = 3.6 x 10-16
e. both c and d.
43. For the reaction: N2(g) + 3H2(g) -<- 2NH3(l), the equilibrium constant expression, Kc, is:
a. Kc = [NH3]2/ [N2][H2]3 / b. Kc = [N2][H2]3/ [NH3]2 / c. Kc = [NH3]/ [N2][H2]
d. Kc = 1/([N2][H2]) / e. Kc = 1/([N2][H2]3)
44. For the reaction: N2(g) + 3H2(g) -<- 2NH3 (l) DHorxn = +250 kJ at 25oC, the equilibrium composition would shift toward product if:
a. the pressure was increased / b. the concentration of H2 was decreased.
c. the temperature was decreased / d. the concentration of N2 was decreased.
e. b and d
45. Given the net ionic equation: HCN(aq) + HS-(aq) -<- CN-(aq) + H2S(aq)
a. HCN is a base; CN- is its conjugate acid. / b.H2S is an acid; HS- is its conjugate base.
c. HS- is a Lewis acid, it is a proton donor. / d. HS- is an acid; CN- is its conjugate base
e. CN- is a Bronsted acid because it is a proton acceptor.
46. Seawater has a pH of 8.10. What is its hydrogen-ion concentration?
a. 1.0 x10-14M / b. 8.0 x 10-8M / c. 7.9 x 10-9M / d. 1.3 x 10-5M / e. 5.90 M
47. Which of the following soluble salts would make an acidic solution when dissolved in water?
a. KCN / b. NH4NO3 / c. NaCl / d. KF / e. a and d
48. The overall order corresponding to the rate law, rate = k[H2]½ [Cl2] , is
a. 1/2 / b. 1st / c. 3/2 / d. 2nd / e. 3rd
49. The correct Ksp expression for the addition of iron(III) sulfide, Fe2S3, to water is:
a. [Fe3+] 3[S2-]2 / b. [Fe3+]2 [S2-]3 / c. [2Fe3+]2 [3S2-]3 / d. [3Fe3+]2 [2S2-]3 / e. [Fe3+]1/2[S2-]1/3
50. If a voltaic cell has a positive Eo value, what can be concluded:
a. DGo< 0, Keq < 1 / b. DGo< 0, Keq > 1 / c. DGo> 0, Keq < 1
d. DGo> 0, Keq > 1 / e. DGo and Keq are not related to the Eo value.
51. According to the 2nd Law of Thermodynamics, for a spontaneous process, the total entropy of the system and surroundings
a. decreases / b. increases / c. is equal to the enthalpy
d. increases if there is no heat exchange
e. may increase of decrease depending on if it is endothermic or exothermic.
52. A gas is heated gaining 75 J of heat, and it expands such that the work out to the surroundings is 45 J. The internal energy change of the gas is:
a. -120 J / b. -30 J / c. +30 J / d. +120J
e. impossible to determine without knowing the initial internal energy.
53. For the redox reaction MnO4-(aq) + F - (aq) -> MnO2(s) + F2(g), the reducing agent for the reaction in the forward direction is:
a. Mn in MnO4- / b. F- / c. O in MnO4- / d. Mn in MnO2 / e. F in F2
54. An example of an electrolytic cell is:
a. a new alkali battery / b. a new nickel-cadmium battery. / c. a hydrogen-oxygen fuel cell.
d. the Downs cell which produces Na / e. a new lead acid battery.
55. Naturally occurring silver (Ag) consists of two isotopes. One of the isotopes, Ag-107 has a mass of 106.90509 amu and a fractional abundance of 51.840%. What is the other isotope?
a. Ag-105 / b. Ag-106 / c. Ag-108 / d. Ag-109 / e. Ag-110
56. The molar solubility of Ag2SO4 is 2.5 x 10-2M. The value of ths solubility product constant is:
a 6.25 x 10-7 / b. 6.25 x 10-5 / c. 1.6 x 10-5 / d. 1.25 x 10-3 / e. 0.75 x 103
57. A 0.1 M solution of HCN is 0.01% ionized, the Ka for HCN is?
a. 10-2 / b. 107 / c. 10-3 / d. 10-9 / e. 10-5
58. The hydrogen halide whose water solution shows the highest acid strength is:
a. HF / b. NH3 / c. HCl / d. HI / e. HBr
59. According to the Lewis Theory of acids and bases, tin(IV) chloride is
a. a base / b. an acid / c. neutral / d. monoprotic / e. polyprotic
60. Silver chloride was precipitated by adding HCl to a solution of silver salt until the concentration of the chloride ions is 0.20M. Ideally the concentration of silver ions would be: (Ksp (AgCl) = 1.56 x 10-10)
a. (1.56 x 10-5)1/2 / b. 7.8 x 10-10 / c. (7.8 x 10-10)1/2 / d. 1.56 x 10-10 / e. 7.8 x 105


61. The reduction potential for the reaction Ag+ + e- -> Ag is 0.80v, and the reduction potential for
Mg2++ 2e- -> Mg is -2.37 V. What is the potential of the reaction occuring in the cell Mg/Mg2+//Ag+/Ag?
a. 3.94V / b. 3.17V / c. -0.77V / d. -3.17V / e. -3.94V
64 64
62. In the following incomplete nuclear equation: 29Cu -> ? + 28 Ni, the ? is
a. an electron / b. a positron / c. a neutron / d. a proton / e. an alpha particle
63. Which of the following is acetic acid (vinigar)?
a. CH3OH / b. CH3CH2OH / c. CH3COH / d. CH3COCH3 / e. CH3COOH
64. How many structural isomers are possible for C4H10?
a. 1 / b. 2 / c. 3 / d. 4 / e. more than 4
65. What is the IUPAC name of (CH3)2CHCH=CHCH3?
a. 1,2-methyl-isopropylethene / b. 1,1-dimethyl-2-butene / c. 1-isopropylpropene
d. 4-methyl-2-pentene / e. 2-methyl-4-pentene
66. Which compound can exist in optically active forms?
a. CH3CH2CH2CH2OH / b. CH3CH2CHOHCH3 / c. (CH3)2CHCH2OH
d. (CH3)3CCH2OH / e. None of these
67. How many different tripeptides can be formed from the amino acids glycine, alanine and valine if each is used only once in each tripeptide?
a. 2 / b. 3 / c. 4 / d. 5 / e. 6
68. Which organic acid is strongest?
a. HCOOH / b. CH3COOH / c. ClCH2COOH
d. ClCH2CH2COOH / e. ClCH2CH2CH2COOH
69. All of the classes of compounds contain at least one oxygen atom EXCEPT
a. ester / b. aldehyde / c. ether
d. alkyne / e. alcohol
70. What is the most characteristic reaction of benzene?
a. addition / b. polymerization / c. reduction
d. substitution / e. elimination

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