17. The equilibrium constant K for the dissociation reaction of a molecule X₂

 X_2(g) ←→ 2X_(g) 

was measured as a function of temperature (in Kelvin). A graph of ln K versus 1/T for this reaction gives a straight line with a slope of –1.352x10⁴ and an intercept of 15.59 K. The value of ∆S for this dissociation reaction is:
(A)1.875 J/K mol
(B)259.2 J/K mol
(C)32.4 J/K mol
(D)64.81 J/K mol
(E)129.6 J/K mol

13. For the reaction CaCO₃(s) ←→ CaO(s) + CO₂(g), Kp = 1.16 at 800.°C. If a 21.1 gram sample of CaCO₃ is put into a 10.0 L container and heated to 800°C, what percent of the CaCO₃ will react to reach equilibrium? (A)32.3%(B)62.5%(C)83.8% (D)41.9%(E)100.0%

14. What is the pH of a solution prepared by mixing 50.0 mL of 0.300 M HCl with 450.0 mL of 0.400 M HIO₃ ? (Ka of HIO₃ = 0.16) (A)1.52(B)0.80(C)0.72 (D)0.89(E)1.10

15. Consider the titration of 100.0 mL of 0.250 M aniline (Kb = 3.8x10-10) with 0.500 M HCl. Calculate the pH of the solution at the stoichiometric point. (A)-0.85(B)8.70(C)2.68 (D)11.62(E)7.00

16. The Kf for the complex ion Ag(NH₃) 2+ is 1.7x107 . The Ksp for AgCl is 1.6x10-10. Calculate the molar solubility of AgCl in 1.0 M NH₃. (A)5.2x10-2 M(B)4.7x10-2 M(C)2.9x10-3 M (D)1.3x10-2 M(E)3.5x10-2 M 

18. An excess of finely divided iron is stirred up with a solution that contains Cu²⁺ ion, and the system is allowed to come to equilibrium. The solid materials are then filtered off and electrodes of solid copper and solid iron are inserted into the remaining solution. What is the value of the ratio [Fe²⁺]/[Cu²⁺] at 25°C? The following standard reduction potentials apply: (A)1(B)1.3x1026(C)2.5x1026 (D)4.4x10-27(E)8.8x10-27

19. Rubidium–87 decays by beta decay with a half-life of 4.9×1010 years. How many 87Rb atoms are in a moon rock sample that has a rubidium decay rate of 3500 disintegrations per hour? (A)9.0×1016 atoms (B)4.3×10⁻⁴ atoms (C) 2.2×1018 atoms (D)2.5×1014 atoms (E)2.6×1015 atoms

20. What two oxidation states are more frequently observed in the first transition series than in the third? (A)+3 and +7 (B)+2 and +3 (C) +2 and +7 (D)+5 and +6 (E)+2 and +5

21. Give the number of geometrical isomers for the octahedral compound [MA₂B₂C₂], where A, B, and C represent ligands. (A)1(B)2(C)3 (D)5(E)6

22. A particular first order reaction has a rate constant of 1.35×10² s⁻¹ at 25.0 °C. What is the magnitude of k at 75.0 °C if Ea = 55.3 kJ/mol? (A)2.24 × 10⁴(B)3.34 × 10³(C)433 (D)1.05 × 10³(E)2.49 × 10⁶

23. For a particular reaction in a galvanic cell ∆S° is negative. Which of the following statements is true? (A)E⁰will increase with an increase in temperature. (B)E⁰will decrease with an increase in temperature. (C) E⁰will not change when the temperature increases. (D)∆G° > 0 for all temperatures. (E)None of these