a. Orange b. Green c. Red d. Yellow e. Colorless, because the crystal field splitting is so large that the absorption is shifted into the ultraviolet

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1. [6 points] The complex [Ni(NH 3 ) 6 ] 2+ has a blue-violet color. What color would you expect for [Ni(H 2 O) 6 ] 2+? a. Orange b. Green c. Red d.

[6 points] How many unpaired electrons are there on a high-spin [Fe(H 2 O) 6 ] 2+ complex ion with octahedral geometry? a. 0 b. 1 c. 3 d. 4 e. 5 3.

[6 points] Consider a voltaic cell based on the following reactions: Cu 2+ (aq) + Zn (s) Zn 2+ (aq) + Cu (s) Which of the following actions would

1 1. [6 points] The complex [Ni(NH 3 ) 6 ] 2+ has a blue-violet color. What color would you expect for [Ni(H 2 O) 6 ] 2+? a. Orange b. Green c. Red d. Yellow e. Colorless, because the crystal field splitting is so large that the absorption is shifted into the ultraviolet 2. [6 points] How many unpaired electrons are there on a high-spin [Fe(H 2 O) 6 ] 2+ complex ion with octahedral geometry? a. 0 b. 1 c. 3 d. 4 e [6 points] Which of the following images is a depiction of the fluorite structure? (a) (b) (c) (d) 4. [6 points] Consider a voltaic cell based on the following reactions: Cu 2+ (aq) + Zn (s) Zn 2+ (aq) + Cu (s) Which of the following actions would decrease the measured cell potential? a. Increasing the size of the zinc anode b. Adding Zn(NO 3 ) 2 to the anode compartment c. Adding CuCl 2 to the cathode compartment d. Adding NaOH to the anode compartment (precipitation rxn) e. None of the above

2 5. [6 points] Consider a voltaic cell where one cell compartment contains NiCl 2 (aq) in contact with a Ni electrode, while the other cell compartment contains ZnCl 2 (aq) in contact with a Zn electrode. Which electrode is the anode and what is the standard cell potential (Eº cell ) for this cell? a. Anode = Zinc, Eº cell = V b. Anode = Nickel, Eº cell = V c. Anode = Zinc, Eº cell = V d. Anode = Nickel, Eº cell = V e. Anode = Zinc, Eº cell = V 6. [6 points] In the above problem what would be the cell potential if the temperature is 298 K, the NiCl 2 concentration is 2.50 M, and the ZnCl 2 concentration is M? a V b V c V d V e V 7. [6 points] Which of the following reactions will occur spontaneously as written? a. 2Fe 2+ (aq) + Cu 2+ (aq) Cu (s) + 2Fe 3+ (aq) b. 2Fe 2+ (aq) + Cu 2+ (aq) Cu (s) + 2Fe (s) c. Pb 2+ (aq) + Cu (s) Cu 2+ (aq) + Pb (s) d. H 2 (g) + Cu 2+ (aq) Cu (s) + 2H + (aq) e. None of the above 8. [6 points] What is the coefficient of Cl - and H 2 O, when the following redox equation is balanced in basic solution? Pb(OH) 4 2- (aq) + ClO - (aq) PbO 2 (s) + Cl - (aq) a. 1 (Cl - ) & 1 (H 2 O) b. 1 (Cl - ) & 3 (H 2 O) c. 2 (Cl - ) & 3 (H 2 O) d. 3 (Cl - ) & 1 (H 2 O) e. 3 (Cl - ) & 2 (H 2 O)

3 9. [6 points] Consider a pure crystalline solid that is heated from absolute zero to a temperature above the boiling point of the liquid. Which of the following processes produces the greatest increase in the entropy of the substance? a. Melting the solid b. Heating the liquid c. Heating the gas d. Heating the solid e. Vaporizing the liquid 10. [6 points] Given the following thermodynamic quantities: Substance ΔHº f (kj/mol) S (J/K mol) Ca (s) CaCl 2 (s) Cl 2 (g) What is the value of ΔGº at 25 ºC for the decomposition of calcium chloride? a kj/mol b kj/mol c kj/mol d kj/mol e kj/mol CaCl 2 (s) Ca (s) + Cl 2 (g) 11. [6 points] CaCl 2 melts at 775 ºC (1048 K). Given your calculations in the previous problem, and assuming that the values of ΔHº f and S do not change with temperature, which of the following statements is true? a. The decomposition of CaCl 2 is spontaneous at all temperatures b. The decomposition of CaCl 2 is spontaneous at temperatures above 5 K c. The decomposition of CaCl 2 is not spontaneous at any temperature d. In theory the decomposition of CaCl 2 would become spontaneous at a temperature much greater than the melting point 12. [6 points] In experiment 26 one of the tests you use to determine the identity of the anion is to look for the formation of gas bubbles upon reaction with acid. Which of the following anions will react with acid to form a gaseous product? a. Cl - b. SO 4 2- c. CO 3 2- d. NO 3 - e. Br -

4 13. [6 points] In Table 26.2 of your lab manual, Colors of Ions in Solution, Ni 2+ is listed both as a green ion and a blue ion. Why is it listed with two colors? a. Because the real color of Ni 2+ in solution is blue-green and it can be hard to tell if it is more blue than green b. [Ni(H 2 O) 6 ] 2+ ions are green, but some complex ions, such as [Ni(NH 3 ) 6 ] 2+ are blue c. Ni 2+ salts are blue, but Ni 2+ ions in solution are green d. The green color comes from Ni 2+ ions with a high-spin octahedral coordination environment, while the blue color corresponds to Ni 2+ ions in a low-spin octahedral environment e. A change in oxidation state is responsible for the change in color 14. [6 points] What is the ph of a saturated solution of Zn(OH) 2 (the K sp of Zn(OH) 2 = )? a. 8.6 b. 5.4 c. 8.8 d. 6.1 e [6 points] The concentration of iodide ions in a saturated solution of lead (II) iodide is M. The K sp for PbI 2 is ? a b c d e [6 points] The molar solubility of is not affected by the ph of the solution. a. Ca 3 (PO 4 ) 2 b. NaF c. PbCl 2 d. MnS

5 17. [6 points] A solution contains chloride and sulfate anions in equal concentrations, 0.20 M. If a dilute Pb(NO 3 ) 2 solution is slowly added to the solution what is the first precipitate to form. The solubility product constants are PbCl 2 (K sp = ) & PbSO 4 (K sp = )? a. PbCl 2 b. PbSO 4 c. Both will begin to precipitate at the same concentration of Pb 2+ d. No precipitates will form 18. [6 points] In the above problem what is the concentration of the less soluble anion, when the more soluble anion begins to precipitate? a M b M c M d M e. None of the above 19. [6 points] In which of the following would you expect AgCl to have the highest solubility? a. Pure water b M BaCl 2 c M NaCl d M AgNO 3 e M KCl

6 Standard Reduction Potentials Half Reaction Eº (V) Cr 3+ (aq) + 3e - Cr (s) Ag + (aq) + e - Ag (s) Fe 2+ (aq) + 2e - Fe (s) Fe 3+ (aq) + e - Fe 2+ (s) Cu 2+ (aq) + 2e - Cu (s) Zn 2+ (aq) + 2e - Zn (s) Ni 2+ (aq) + 2e - Ni (s) Pb 2+ (aq) + 2e - Pb (s) Sn 4+ (aq) + 2e - Sn 2+ (aq) Sn 2+ (aq) + 2e - Sn (s) H + (aq) + 2e - H 2 (g) BiO + (aq) + 2H + (aq) + 3 e - Bi (s) + H 2 O Spectrochemical Series Weak Field Cl - < F - < H 2 O < NH 3 < NO - 2 < CN - Strong Field Ligands Ligands Physical Constants & Conversion Factors h = J-s c = m/s R = J/K-mol 1 Å = 10 pm = m 1 ev = J 1 F = 96,500 C/mol = 96,500 J/V-mol 1 A = 1 C/s 1 ev = J

7 Approximate Wavelengths and Energies of the Visible Spectrum Violet nm ev Blue nm ev Green nm ev Yellow nm ev Orange nm ev Red nm ev Equations E = hc/λ = {(6.626 x J-s)(2.998 x 108 m/s)}/λ ΔG = ΔH - TΔS ΔGº rxn = ΣnΔG º f(products) - ΣmΔG º f(reactants) ΔG = ΔGº + RT ln(q) K eq = exp[-δgº/rt] E = Eº - (RT/nF) ln(q) E = Eº - (0.0592/n) ln(q) Log K eq = neº/ at T=298 K at T=298 K

4. [7 points] Which of the following reagents would decrease the solubility of AgCl(s)? NaOH HCl NH 3 NaCN

4. [7 points] Which of the following reagents would decrease the solubility of AgCl(s)? NaOH HCl NH 3 NaCN 1. [7 points] It takes 0.098 g of silver iodate, AgIO 3, to make 1.00-L of a saturated solution saturated at 25 C. What is the value of the solubility product, K sp? a. 3.5 10 4 b. 1.2 10 7 c. 9.8 10 2