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General Chemistry II Sample Test bank Page 1 of 18 3 l OM oARc PSD|13 72 1 45 2
CHEM 1128 ACS FINAL
EXAM PRACTICE
|159Qs&As|ANSWERS ON
THE LAST
PAGE|A+GRADE
1. According to the Bronsted—Lowry definition, which chemical species can function both as an acid and as a base? a. Cl— b. SO 42 — c. NH 4 + 8. The weakest of the bases listed is d. HCO — e. H 3 O+ 2. In the reaction CN—^ + H 2 O HCN + OH— which is an acid—base conjugate pair? a. H 2 O and HCN b. H 2 O and OH— c. CN—^ and H 2 O d. HCN and OH— 3. Given that HX is a stronger Bronsted acid than HY in aqueous solution, which is true of a 1 M solution 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 is a. 1. b. 2. c. 3. d. 12. a. Cl— b. CN— c. HS— d. S^2 — e. SO 42 — 9. The oxide of which element will react with water to 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. W b. M c. P d. R e. Z
5. The pH of a 1.0 x 10—^3 M Ba(OH) 2 solution at 25 oC is a. 2. b. 3. c. 11. d. 11. 6. Which is the strongest acid? a. HClO b. HClO 2 c. HClO 3 d. HClO 4 7. Which salt reacts with water (hydrolyzes) to produce a basic solution? a. NaC 2 H 3 O 2 b. NaNO 3 c. NH 4 Cl d. BaSO 4 Acid Conjugate Base Ka (Ionization Constant of Acid) HCl Cl—^ 100% ionized HSO 4 — SO 42 —^ 1.2 x 10-^2 H 2 S HS—^ 5.7x10-^8 HS—^ S^2 —^ 1.2x10-^13
General Chemistry II Sample Test bank Page 2 of 18
10. Which statement is a logical inference from the fact that a 0.10 M solution of potassium acetate KC 2 H 3 O 2 , is less alkaline than a 0.10 M solution of potassium cyanide, KCN? a. Hydrocyanic acid is a weaker acid thanacetic acid. b. Hydrocyanic acid is less soluble in waterthan acetic acid. c. Cyanides are less soluble than acetates d. Acetic acid is a weaker acid thanhydrocyanic acid 11. In the titration of 50.0 mL of 0.100 M benzoic acid (a monoprotic acid) with 50. mL of 0.100 M NaOH, the properties of the solution at the equivalence point will correspond exactly to the properties of a. 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.
General Chemistry II Sample Test bank Page 4 of 18
25. The number of bonds in N=N is a. 1 b. 2 c. 3 d. 4 26. The elements in an ionic compound are held together by (^) 31. Using only the metals Mg, Al, Zn, Fe, Cu a. electrostatic forces of attraction. b. van der Waals forces c. 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 solution containing cations of X. The passage of 48.25 C deposited 31 mg of X on the cathode. What is the mass of X (in grams) per mole of electrons? a. 47 b. 62 c. 93 d. 186 29. In a galvanic (voltaic) cell in which the reaction is Cd + Cu2+^ Cu + Cd2+ and the ions are at unit concentration (activity), the cell potential is Cd Cd2++ 2e-^ 0.4021 V Cu Cu2+^ + 2e-^ - 0.344 V a. 0.1383 V b. 0.4021 V c. 0.344 V d. 0.7461 V e. 0.3677 V 30. In which reaction will an increase in total pressure at constant temperature favor formation of the products? a. CaCO 3 (s) CaO(s) + CO 2 (g) b. H 2 (g) + Cl 2 (g) 2HCl(g) c. 2NO(g) + O 2 (g) 2NO 2 (g) d. COCl 2 (g) CO(g) + Cl 2 (g) and Ag, together with their 1 M salt solutions, a voltaic cell of the highest possible voltage would be constructed using electrodes of these metals. a. Mg and Ag b. Mg and Fe c. Zn and Cu d. Al and Ag e. Mg and Al 32. E = Eo^ - 0.059/n log Q (Nernst equation) [H+] = 1.0 M initially, P 02 = 1.0 atm 4e + O 2 (g)+4H+(aq) 2H 2 O(l) Eo=1.23V Based on the information above, which statement is 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 = [H 2 O]^2 [O 2 ] [H+] 33. The equilibrium constant for the gaseous reaction C + D E + 2F is 3.0 at 50 o C. In a 2.0 L flask at 50 o C are placed 1.0 mol of C, 1. mol of D, 1.0 mol of E, and 3.0 mol of F. Initially, the reaction will a. 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 Gof kJ/mol H 2 O(l) — 237 H 2 O(g) — 229 34. At 298 K the equilibrium constant for H 2 (g) + ½ O 2 (g) H 2 O(l) a. is larger than the Keq for H 2 (g) + ½ O 2 (g) H 2 O(g) b. will have a value of 1 0 at equilibrium. c. cannot be computed since data on O 2 and Standard Potentials Eo Mg Mg2++2e 2.37V Al Al3++3e 1.66V Zn Zn2++2e 0.76V FeFe2++2e 0.44V Cu Cu^2 + + 2 e 0.34V Ag Ag++ e - 0.80V
General Chemistry II Sample Test bank Page 5 of 18 H 2 are not provided. d. will have the same value as the Keq for 2 H 2 (g) + O 2 (g) 2 H 2 O(l)
35. Consider the reversible system at equilibrium: 2CO + O 2 2CO 2 + heat When the temperature is increased at constant pressure a. the CO 2 concentration will be increased. b. the CO 2 concentration will be decreased. c. the amount of each substance will be unchanged. d. the amount of each substance will be increased. e. the result cannot be predicted from the information given. 36. The numerical value of the equilibrium constant for any chemical change is affected by changing a. 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 CO 2 by O 2? a. K = [CO 2 ]^2 [CO][O 2 ] b. K= [CO]^2 [O 2 ] [CO 2 ] c. K= [CO 2 ]^2 [CO]^2 [O 2 ] d. K= [CO] [O 2 ] [CO 2 ] 38. Into an empty vessel COCl 2 (g) is introduced at 1.0 atm pressure whereupon it dissociates until equilibrium is established: 2COCl 2 (g) C (graphite) + CO 2 (g) + 2Cl 2 (g) If x represents the partial pressure of CO 2 (g) at equilibrium, what is the value of the equilibrium constant, Kp? a. x.2x^2 (1.0-2x)^2 b. x x 2x^2 (1.0-2x^2 ) c. x (2x)^2 (1.0- 2x)^2 d. x (2x)^2 (1.0—x)^2 39. At a certain temperature, the equilibrium constant for the reaction 2HI(g) H 2 (g) + I 2 (g) is 0.49. Calculate the number of moles of hydrogen produced when one mole of HI is placed in a 1 L vessel at this temperature. a. 0. b. 0. c. 0. d. 3. 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. b. 3. c. 5. d. 6. 42. When 0.10 mol of a weak acid HA was diluted to one liter, experiment showed the acid to be 1% dissociated. HA + H 2 O H 3 O+^ + A- What is the acid dissociation constant, Ka? a. 1 x10-^6 b. 1 x10-^5 c. l x10-^3 d. 1 x10^5 43. Which solution has a pH less than 7.0? a. 1 M NH 4 Cl b. 1 M K 2 CO 3 c. 1 M NaOCl d. 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. b. 5. c. 8. d. 9.
General Chemistry II Sample Test bank Page 7 of 18
56. According to the kinetic molecular theory, a. gaseous molecules are continuously in random 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 the speed of its molecules. d. gaseous molecules can travel in straight or curved paths. e. all gaseous molecules are diatomic. 57. The volume of a given mass of gas varies inversely with pressure, provided that the temperature remains constant because a. attractive forces between gas molecules are negligible. b. attractive forces between gas molecules are appreciable. c. the average kinetic energy of the molecules of a gas is proportional to the absolute temperature. d. increasing the molecular concentration, at constant temperature, means increasing the number of collisions between molecules and container. e. collisions between gas molecules are perfectly elastic. 58. The Kelvin temperature of one liter of gas is doubled and its pressure is tripled, volume will then be a. l/ 6 L b.^2 / 3 L c.^3 / 2 L d. 6 L 59. Which gas, present in the same closed system, has the greatest average kinetic energy at a given temperature? a. Hydrogen b. neon c. carbon dioxide d. None; the average kinetic energy is the same for each gas. 60. A sample of neon occupies a volume of 27.3 L at STP. What would be the neon volume at 177 oC and 0.100 atm pressure? a. 177 L b. 350 L c. 422 L d. 450 L 61. Under the same conditions of temperature and pressure, the gas whose molecules possess the highest average speed is a. H 2 O b. O 2 c. F 2 d. Ne 62. What is the volume of 2.00 mol of helium gas at 27 oC and 3.00 atm? a. 6.1x10-^2 L b. 1.48L c. 16.4L d. 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 mass of 0.9825 g at 0oC and 760 mmHg. What is the approximate molar mass of the compound? a. 19. b. 38. c. 44. d. 58. 65. The partial pressures of a gaseous mixture are given in the table. What is the mole percent of hydrogen? Partial Pressures hydrogen 200 mmHg carbon dioxide 150 mmHg methane 320 mmHg ethylene 105 mmHg a. 20. b. 25. c. 38. d. 41.
General Chemistry II Sample Test bank Page 8 of 18 2 2 2 6 6 6 6 2 3
66. It is desired to collect enough oxygen over water at 25 oC and 750 mmHg barometric pressure to be equivalent to 1 L of pure oxygen at 0 oC and 760 mmHg. The vapor pressure of water at 25 oC is 23.5 mm. The volume collected is a. 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, CH 4 , diffuses in a given apparatus at the rate of 30 mL/min. At what rate would a gas with a molar mass of 100 diffuse under the same conditions? MW of CH 4 = 16 g/mol a. 0.77 mL/min b. 30 mL/min c. 6.7 mL/min d. 75 mL/min e. 12.0 mL/min 68. The Arrhenius equation, k= Ae-E/RT expresses the relationship between the reaction rate constant, k, and the energy of activation, E_._ The probability that colliding molecules will react a. increases with increasing energy of activation. b. depends only on the empirical constant, A. c. increases with decreasing temperature. d. decreases with increasing energy of activation. 69. The rate law for the reaction A+BC+D is first order in [A] and second order in [B]. If [A] is halved and [B] is doubled, the rate of the reaction will a. remain the same b. 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 reaction a. 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: CH 3 CH 2 Br + AlBr 3 AlBr 4 -^ + CH 3 CH + CH 3 CH +^ + C H C H CH CH + C 6 H 6 CH 2 CH 3 +^ + AlBr 4 -^ AlBr 3 + HBr + C 6 H 5 CH 2 CH 3 Which substance serves as the catalyst? a. AlBr 3 b. CH 3 CH + c. AlBr 4 - d. C 6 H 6 CH 2 CH 3 + 72. Which substance has the highest boiling point? a. CH 4 b. He c. HF d. Cl 2 73. The table presents data for the reaction: The temperature of the reaction is constant. The initial rate is in arbitrary units. 2H 2 (g) + 2NO(g) 2H 2 O(g) + N 2 (g) Initial Concentration (mol/L) Exp. [NO] x 10 -^3 [H 2 ] x 10 -^3 Initial Rate I 6.0 1.0 18 II 6.0 2.0 36 III 1.0 6.0 3 IV 2.0 6.0 12 What is the rate law for this reaction? a. rate = k 1 [H 2 ][NO] b. rate = k 1 [H 2 ]^2 [NO]^2 c. rate = k 1 [H 2 ]^2 [NO] d. rate = k 1 [H 2 ] [NO]^2 74. The reaction 2A + 2B C +D proceeds by this mechanism: 2A A 2 (equilibrium) A 2 + B X + C (rate determining) X+BD (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]
General Chemistry II Sample Test bank Page 10 of 18 Br 3 3
85. The fact that BCl 3 is a planar molecule while NCl 3 is pyramidal can be explained several different ways. Which is the best rationalization? a. Nitrogen is more electronegative than boron. b. The nitrogen atom in NCl 3 has a lone pair of electrons whereas the boron atom in BCl 3 does not. c. The nitrogen atom is smaller than the boron atom d. The boron atom in BCl 3 is sp^3 hybridized, while the nitrogen atom in NCl 3 is sp^2 hybridizes 86. The geometry for SeF +^ is a. trigonal pyramidal. b. tetrahedral. c. square planar. d. rectangular planar. 87. The Lewis structure of BrF 5 is F F F F F The molecular structure of BrF 5 is a. square pyramidal. b. trigonal pyramidal. c. trigonal bipyramidal. d. octahedral. 88. Which is planar? a. PCl 3 b. ClO - c. CO 32 - d. NH 3 e. PH 3 89. A molecule of the type ML 4 consists of four bonding pairs of electrons and no lone pairs. Which structure would it be expected to assume? a. square planar b. tetrahedral c. linear d. square pyramidal 90. A sample of a radioactive isotope initially contains 20 x 10^10 atoms. After 16 days, 5 x 10^10 atoms remain. What is the half-life of the isotope? a. 4 days b. 8 days c. 12 days d. 16 days 91. Which of these molecules is the most polar? (X and Y are two different elements, Y being the more electronegative.) a. X 2 b. Y 2 c. X—Y—X d. X—Y X X e. Y—X X 92. In the beta emission of a species such as (^146) C 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 (methane series) hydrocarbon? a. C 5 H 12 b. C 5 H 11 OH c. (C 2 H 5 ) 2 O d. C 6 H 6 e. C 6 H 5 Cl 94. lsobutane differs from butane in that the former 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 C 4 H 10 b. n-heptane C 7 H 16 c. n-hexane C 6 H 14 d. n-pentane C 5 H 12
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96. The reaction between acetic acid and ethyl alcohol is classified as CH 3 COOH + C 2 H 5 OH CH 3 COOC 2 H 5 + H 2 O a. b. c. d. the magnesium acts as a reducing agent. How many electrons does each magnesium atom lose? 97. in a. [MnF 6 ]^3 - b. Mn 2 O 7 c. [MnO 4 ]^2 - d. [Mn(CN) 6 ]^1 - 98. The highest oxidation number of vanadium is exhibited in a. VO2+ b. VBr 4 c. NH 4 VO 3 d. V 2 (SO 4 ) 3 e. V(CN) 63 — 99. Fe(s) + Cu2+^ (aq) Cu(s) + Fe2+^ (aq) Which statement is true for the reaction? a. Cu2+^ is oxidized. b. Cu2+^ gains in oxidation state. c. Cu2+^ is reduced. d. Fe(s) is reduced. 100. Which is the strongest oxidizing agent? most polarizable? a. Na+ b. O^2 - c. F- d. Mg2+ 103. The greatest oxidizing power (tendency to gain electrons) is shown by Standard Potentials Eo Na Na+^ + e 2.714 V Al Al3++3e 1.67 V Sn2+Sn4++2e - 0.14 V 21 —^ l 2 +2e - 0.535 V 2F—F 2 + 2e - 2.85 V a. Na+ b. Al c. Sn4+ d. F 2 104. Which metal will reduce copper(ll) ions but not zinc ions? Standard Potentials Eo Na Na+^ + e 2.71 V Cd Cd2+^ + 2e 0.40 V H 2 2H+^ + 2e 0.00 V Ag Ag+^ + e - 0.80 V a. Na+ b. H 2 c. Cd^0 d. Ag+ 101. In this reaction 3Mg + 2HNO 3 (dilute) + 6H 3Mg2+^ + 2NO + 4H 2 O a. Na b. Hg c. Pb d. Ag Standard Potentials Eo Na Na+^ +e 2.71 V Zn Zn2++2e 0.76 V Fe Fe2+^ + 2e 0.4 V Pb Pb2++2e 0.13 V H 2 2H+ + 2e 0.00 V Cu Cu2++2e - 0.34.V Hg Hg2++2e - 0.85 V Ag Ag+^ +e - 0.80 V a. 1 saponification b. 2 addition c. 3 esterification d. 4 hydrolysis e. 6 Manganese has the oxidation number of +5 102. Which of these isoelectronic ions is the
General Chemistry II Sample Test bank Page 13 of 18
117. If 0.400 g of a substance R (MW = 80. g/mol) is dissolved in 100 g of liquid Q, what is the molality of the solution? a. 4.00x10–^3 m b. 5.00x10–^2 m c. 5.00 x 10 –^3 m d. 4.00 x 10 –^1 m 118. What is the mole fraction of water in 200. g of 95% (by mass) ethanol, C 2 H 5 OH (mw = 46. g/mol)? a. 0. b. 0. c. 0. d. 0. 119. A 0.10 m aqueous solution of HF shows a freezing point of - 0.198 oC. What is the percent dissociation of HF? Molal freezing point constant, Kf for water = 1 .86 oC/m a. 6.4% b. 10% c. 20% d. 98% 120. A 0.10 m solution of MgSO 4 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 smallest freezing point depression? a. 0.2 m Ca(NO 3 ) 2 b. 0.2 m MgSO 4 c. 0.2 m CH 3 OH d. 0.2 m K 3 PO 4 122. When one mole of naphthalene is dissolved in 1000 g of benzene, the freezing point changes from 5.51 oC to 0.41 oC. When 20 g of an unknown organic compound is dissolved in 500 g of benzene, the freezing point of this solution is 5.00 oC. What is the molar mass of the unknown organic compound? a. 40 g./mol b. 200 g/mol c. 100 g./mol d. 400 g/mol e. 128 g./mol 123. When dilute aqueous solutions of lead(II) nitrate and potassium bromide are mixed, a precipitate is observed. The products of this reaction are a. Pb2+(aq) + Br 1 -^ (aq) + KNO 3 (s) b. Br 2 (aq) + NO 2 (g) + PbK 2 (s) c. PbO(s) + K+(aq) + Br^1 - (aq) + NO 2 (g) d. PbBr 2 (s) + K+(aq) + NO 3 1 - (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 23 oC? Vapor Pressure @ 23 oC Carbon tetrachloride 100. mm Hg Dioxane 38.00 mm Hg a. 50.4 mmHg b. 62.8 mmHg c. 74.2 mmHg d. 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. Na 3 BO 3 b. Na 4 BO 4 c. Na 2 B 2 O 3 d. NaB 2 O 2 126. A hydrocarbon undergoes complete combustion to give 0.44g of CO 2 and 0.27 g of H 2 O. What is the simplest (empirical) formula of the hydrocarbon? a. C 44 H 27 b. CH 4 c. C 2 H 3 d. CH 3
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127. A 6.80 g coin was dissolved in nitric acid and 6.21 g of AgCl was precipitated by the addition 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 MgSO 4 solution contains how many grams of MgSO 4? a. 120 g 133. Which change is likely to be accompanied by the greatest increase in entropy? a. N 2 (g) + 3H 2 (g) 2NH 3 (g) (at 25 oC ) b. Ag+(aq) + Cl^1 - (aq) AgCl(s) (at 25 oC ) c. CO 2 (s) CO 2 (g) (at - 70 oC ) d. H 2 O(g) H 2 O(l) (at 100 oC) 134. When 45.0 g of an alloy at 100.0 oC is dropped into 100.0 g of water at 25.0 oC the final temperature is 37.0 oC. What is the specific heat of the alloy? (for water, specific heat = 4.184 J g- 1 oC- (^1) ) b. 24 g a. 0.423 J g-^1 oC-^1 c. 0.96 g b. 1.77 J g-^1 oC-^1 d. 0.6 g c. 9.88 J g-^1 oC-^1 e. 0.48 g d. 48.8 J g-^1 oC-^1 129. An aqueous solution containing 49 g of 135. What is the standard enthalpy of sulfuric acid per liter has a concentration of a. 0.50 M b. 1.0M c. 4.9% by mass d. 4.9M 130. One hundred milliliters of a solution of oxalic acid, (COOH) 2 , is neutralized with 50. mL of 0.750 M KOH solution. What is the molarity of the oxalic acid solution? a. 0.099 M b. 0.375 M c. 0.188 M d. 0.750 M e. 0.333 M 131. How many L of CO 2 gas at STP can be obtained by burning one mole of C 3 H 8? C 3 H 8 (g) + 5 O 2 (g) 3 CO 2 (g) + 4H 2 O(g) a. 11. b. 44. c. 67. d. 112 132. What volume of ammonia gas, NH 3 , measured at STP, will be produced by the decomposition of two moles of ammonium carbonate? (NH 4 ) 2 CO 3 (s) 2NH 3 (g) + CO 2 (g) + H 2 O(g) a. 22.4 L b. 33.6 L c. 44.8 L d. 89.6 L e. 112 L combustion of C 2 H 6 in kJ mol-^1? Reaction Ho H2(g) + ½ O2(g) H 2 O(l) - 286 kJ C 2 H4(g) + H2(g) C 2 H6(g) - 137 kJ C 2 H 4 (g) + 3 O2(g) 2 CO2(g) + 2 H 2 O(g) - 1412 kJ a. – 1275 kJ b. – 31561 kJ c. – 1558 kJ d. +1834 kJ 136. Given these equations SO 2 (g) O 2 (g) + S (s) Ho^ = +300 kJ 2SO 2 (g) + O 2 (g) 2SO 3 (g) Ho^ = - 200 kJ calculate the heat of formation of SO 3 (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 one gram of steam at 100 oC to water at 50 oC than from cooling one gram of liquid water at 100 oC 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.
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147. Uranium—234 undergoes spontaneous radioactive decay to give an alpha particle and a new nucleus, X. (^234) U 4 He + X What is X? 150. Consider the phase diagram of a pure compound. Which statement applies? 230 90 230 90 238 94 238 94 148. Which is classified as an alkene? O a. CH 3 —CH 2 —C—H b. CH 3 CH 2 CH 3 c. CH 3 —C = C H d. CH 2 HC CH 2 HC CH 2 CH 2 149. An example of an organic acid is O a. CH 3 CH 2 COCH 3 O b. CH 3 CH 2 COH O c. CH 3 CH 2 CNH 2 O d. CH 3 CH 2 CH Temperature a. The path A C represents sublimation. b. Following the path A B C the compound would first liquefy and then vaporize. c. If the compound is in state A, continued reduction of the pressure (at constant temperature) will cause it to melt. d. None of these statements is correct. 151. Which is the formula of an alcohol? a. CH 3 CH 2 CH 2 —O—CH 3 b. CH 3 CH 2 CH 2 CH 2 – O H O c. CH 3 CH 2 —C—CH 3 O d. CH 3 CH 2 CH 2 C—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 0 oC 20 oC 50 oC 80 oC 95 oC 100 oC n-propanol 3.4 14.5 87.2 376 697 836 Water 4.6 17.6 92.0 354.9 760 Turpentine 2.1 4.4 17.0 61.3 131. 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.
A C
B
a. b. c. d.
U
Th U Pu
P
General Chemistry II Sample Test bank Page 17 of 18 B
A
153. For the reaction 2H 2 O 2 2H 2 O +O 2 Which plot confirms that the rate is first order with respect to H 2 O 2? a. [H 2 O 2 ] b. 1/[H 2 O 2 ] c. [H 2 O 2 ]^2 d. log[H 2 O 2 ] time time time time 154. Sulfur dioxide can be described by the structures: S S O O O O This implies that a. the two bonds in SO 2 are of equal length, and the electronic distribution in the two SO bonds is identical. b. the single bond is longer than the double bond and the electronic distribution in the two SO bonds is different. c. an electron pair in the SO 2 molecule alternates back and forth between the two sulfur— oxygen electron pairs so that the two different bonds seem to exchange positions. d. the SO 2 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 of liquid B is 78 0 C.” 1000 900 800 600 400 300 200 100 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. Vapor pressure mm Hg
General Chemistry II Sample Test bank Page 19 of 18 Key to Answers Q # Ans Q # Ans Q# Ans Q# Ans Q# Ans 1 D 2 B
36 E
37 C
71 A
72 C
106 D
107 B
141 A
142 B
3 A 38 C 73 D 108 A 143 C
4 A 39 C 74 D 109 A 144 D
5 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 A
16 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 D
28 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
33 C
34 A
35 B
67 E
68 D
69 B
70 C
102 B
103 D
104 C
105 A
137 E
138 D
139 B
140 B
