Revision of Chapter Six Chapter Six 1 Complete

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Revision of Chapter Six

Revision of Chapter Six

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using the smallest whole-number coefficients, the coefficient of S is H 2 S + HNO 3 S + NO (acidic solution) a) 1 +1 x 2 -2 b) 2 d) 5 e) 6 H 2 S + HNO 3 → S +NO 0 oxidation H 2 S → S +2 e +1 +5 -2 x 3 c) 3 H 2 S → S +2 e + 2 H+ +2 -2 reduction 3 e+ HNO 3 → NO x 3 3 H++ 3 e+HNO 3 → NO + 2 H 2 O 3 H 2 S → 3 S + 6 e + 6 H+ x 2 6 H+ + 6 e + 2 HNO 3 → 2 NO + 4 H 2 O 3 H 2 S + 2 HNO 3→ 3 S + 2 NO + 4 H 2 O

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using the smallest whole-number coefficients, the coefficient of S is H 2 S + HNO 3 S + NO (acidic solution) a) 1 2. b) 2 c) 3 d) 5 e) 6 Given the following notation for an electrochemical cell Pt(s) | H 2(g) | H+(aq) || Ag+(aq) | Ag(s), what is the balanced overall (net) cell reaction? a) 2 H+(aq) + 2 Ag+(aq) H 2(g) + 2 Ag(s) b) H 2(g) + 2 Ag(s) H+(aq) + 2 Ag+(aq) c) 2 H+(aq) + 2 Ag(s) H 2(g) + 2 Ag+(aq) d) H 2(g) + Ag+(aq) H+(aq) + Ag(s) e) H 2(g) + 2 Ag+(aq) 2 H+(aq) + 2 Ag(s) H 2(g)→ 2 H+ (aq) + 2 e+ 2 Ag+(aq) → 2 Ag (s) H 2(g) + 2 Ag+(aq)→ 2 H+(aq) + 2 Ag(s)

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using the smallest whole-number coefficients, the coefficient of S is H 2 S + HNO 3 S + NO (acidic solution) a) 1 2. b) 2 c) 3 d) 5 e) 6 Given the following notation for an electrochemical cell Pt(s) | H 2(g) | H+(aq) || Ag+(aq) | Ag(s), what is the balanced overall (net) cell reaction? a) 2 H+(aq) + 2 Ag+(aq) H 2(g) + 2 Ag(s) b) H 2(g) + 2 Ag(s) H+(aq) + 2 Ag+(aq) c) 2 H+(aq) + 2 Ag(s) H 2(g) + 2 Ag+(aq) d) H 2(g) + Ag+(aq) H+(aq) + Ag(s) e) H 2(g) + 2 Ag+(aq) 2 H+(aq) + 2 Ag(s) 3. Calculate the value of E cell for the following reaction: 2 Au(s) + 3 Ca 2+(aq) 2 Au 3+(aq) + 3 Ca(s) a) -4. 37 V b) -1. 37 V c) -11. 6 V d) 1. 37 V e) 4. 37 V

Chapter Six 3. Calculate the value of E cell for the following reaction: 2

Chapter Six 3. Calculate the value of E cell for the following reaction: 2 Au(s) + 3 Ca 2+(aq) 2 Au 3+(aq) + 3 Ca(s) a) -4. 37 V b) -1. 37 V c) -11. 6 V 2 Au(s)→ 2 Au+3 (aq) + 6 e E°= -1. 50 6 e + 3 Ca+2(aq) → 3 Ca(s) E°=-2. 87 d) 1. 37 V e) 4. 37 V

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using

Chapter Six 1. Complete and balance the following redox equation. When properly balanced using the smallest whole-number coefficients, the coefficient of S is H 2 S + HNO 3 S + NO (acidic solution) a) 1 2. b) 2 c) 3 d) 5 e) 6 Given the following notation for an electrochemical cell Pt(s) | H 2(g) | H+(aq) || Ag+(aq) | Ag(s), what is the balanced overall (net) cell reaction? a) 2 H+(aq) + 2 Ag+(aq) H 2(g) + 2 Ag(s) b) H 2(g) + 2 Ag(s) H+(aq) + 2 Ag+(aq) c) 2 H+(aq) + 2 Ag(s) H 2(g) + 2 Ag+(aq) d) H 2(g) + Ag+(aq) H+(aq) + Ag(s) e) H 2(g) + 2 Ag+(aq) 2 H+(aq) + 2 Ag(s) 3. Calculate the value of E cell for the following reaction: 2 Au(s) + 3 Ca 2+(aq) 2 Au 3+(aq) + 3 Ca(s) a) -4. 37 V b) -1. 37 V c) -11. 6 V d) 1. 37 V e) 4. 37 V

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg 2+ || NO 3 - (acid soln)| NO(g) | Pt a) 3. 33 V b) 1. 41 V Mg(s)→ Mg+2 (aq) + 2 e 2 e + NO 3 -(aq) → NO(g) E°= -2. 37 E°= 0. 96 c) -1. 41 V d) 8. 46 V e) -8. 46 V

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg 2+ || NO 3 - (acid soln)| NO(g) | Pt a) 3. 33 V 5. b) 1. 41 V c) -1. 41 V d) 8. 46 V e) -8. 46 V The overall reaction 2 Co 3+(aq) + 2 Cl-(aq) 2 Co 2+(aq) + Cl 2(g) has the standard cell voltage E cell= 0. 46 V. Given that Cl 2(g) + 2 e- 2 Cl-(aq), E = 1. 36 V, calculate the standard reduction potential for the following the half reaction at 25 C: Co 3+ + e- Co 2+ a) 1. 82 V b) -0. 90 V c) 0. 90 V d) -1. 82 V 2 Co 3+(aq) + 2 Cl-(aq) 2 Co 2+(aq) + Cl 2(g) 2 Cl-(aq)→ Cl 2 (aq) + 2 e 2 e +2 Co+3(aq) → 2 Co+2(s) - e) -1. 36 V

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg 2+ || NO 3 - (acid soln)| NO(g) | Pt a) 3. 33 V 5. c) -1. 41 V d) 8. 46 V e) -8. 46 V The overall reaction 2 Co 3+(aq) + 2 Cl-(aq) 2 Co 2+(aq) + Cl 2(g) has the standard cell voltage E cell= 0. 46 V. Given that Cl 2(g) + 2 e- 2 Cl-(aq), E = 1. 36 V, calculate the standard reduction potential for the following the half reaction at 25 C: Co 3+ + e- Co 2+ a) 1. 82 V 6. b) 1. 41 V b) -0. 90 V c) 0. 90 V d) -1. 82 V e) -1. 36 V In the following half equation, which is the oxidizing agent? NO 3 -(aq) + 4 H+(aq) + 3 e- NO(g) + 2 H 2 O a) NO 3 - b) H+ c) e+5 -2 x 3 +1 d) NO +2 -2 NO 3 -(aq) + 4 H+(aq) + 3 e- NO(g) + 2 H 2 O e) H 2 O

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg

Chapter Six 4. Calculate the standard cell emf for the following cell: Mg |Mg 2+ || NO 3 - (acid soln)| NO(g) | Pt a) 3. 33 V 5. d) 8. 46 V e) -8. 46 V b) -0. 90 V c) 0. 90 V d) -1. 82 V e) -1. 36 V In the following half equation, which is the oxidizing agent? NO 3 -(aq) + 4 H+(aq) + 3 e- NO(g) + 2 H 2 O a) NO 37. c) -1. 41 V The overall reaction 2 Co 3+(aq) + 2 Cl-(aq) 2 Co 2+(aq) + Cl 2(g) has the standard cell voltage E cell= 0. 46 V. Given that Cl 2(g) + 2 e- 2 Cl-(aq), E = 1. 36 V, calculate the standard reduction potential for the following the half reaction at 25 C: Co 3+ + e- Co 2+ a) 1. 82 V 6. b) 1. 41 V b) H+ c) e- d) NO e) H 2 O Which statement is true for a spontaneous redox reaction carried out at standard-state conditions? a) E red is always negative. b) E cell is always positive c) E ox is always positive d) E red is always positive

Chapter Six 8. Consider the following standard reduction potentials in acid solution: The strongest

Chapter Six 8. Consider the following standard reduction potentials in acid solution: The strongest oxidation agent among those shown above is a) Fe 3+ 9. b) Fe 2+ c) Br - d) Al 3+ e) Al Determine the equilibrium constant, Keq, at 25 C for the reaction: 2 Br- (aq) + I 2(s) a) 5. 7 10 -19 b) 18. 30 c) 1. 7 1054 d) 1. 9 1018 e) 5. 7 10 -55 Br 2(l) + 2 I- (aq)

Chapter Six 9. Determine the equilibrium constant, Keq, at 25 C for the reaction:

Chapter Six 9. Determine the equilibrium constant, Keq, at 25 C for the reaction: 2 Br- (aq) + I 2(s) a) 5. 7 10 -19 b) 18. 30 c) 1. 7 1054 2 Br - (aq)→ Br 2(l) + 2 e E°= -1. 07 2 e + I 2(S) → 2 I -(aq) E°=0. 53 E°= -0. 54 , n= 2, T=25+273=298, R=8. 314, F=96500 d) 1. 9 1018 e) 5. 7 10 -55 Br 2(l) + 2 I- (aq)

Chapter Six Consider the following standard reduction potentials in acid solution: 8. The strongest

Chapter Six Consider the following standard reduction potentials in acid solution: 8. The strongest reducing agent among those shown above is a) Fe 3+ b) Fe 2+ c) Br - d) Al 3+ e) Al Determine the equilibrium constant, Keq, at 25 C for the reaction: 2 Br- (aq) + I 2(s) 9. a) 5. 7 10 -19 10. b) 18. 30 c) 1. 7 1054 d) 1. 9 1018 e) 5. 7 10 -55 d) 5. 1 1013 e) None of these Given the following standard reduction potentials, Ag+(aq) + e → Ag(s) Ag. CN(s) + e → Ag(s)+ CN- (aq) E°=0. 80 V E°=-0. 01 V Calculate the solubility product of Ag. CN at 25 C a) 4. 3 10 -14 b) 2. 3 1013 c) 2. 1 10 -14 Br 2(l) + 2 I- (aq)

Chapter Six 10. Given the following standard reduction potentials, Ag+(aq) + e → Ag(s)

Chapter Six 10. Given the following standard reduction potentials, Ag+(aq) + e → Ag(s) E°=0. 80 V Ag. CN(s) + e → Ag(s)+ CN- (aq) E°=-0. 01 V Calculate the solubility product of Ag. CN at 25 C a) 4. 3 10 -14 b) 2. 3 1013 c) 2. 1 10 -14 Ag+(aq) + e → Ag(s) E°=0. 80 V Ag. CN(s) + e → Ag(s)+ CN (aq) E°= - 0. 01 V Ag(s) → Ag+(aq) + e E°= - 0. 80 V Ag. CN(s) + e → Ag(s)+ CN (aq) E°= - 0. 01 V Ag. CN(s) → Ag+(aq)+ CN- (aq) d) 5. 1 1013 e) None of these E°= -0. 81 , n= 1, T=25+273=298, R=8. 314, F=96500

Chapter Six Consider the following standard reduction potentials in acid solution: 8. The strongest

Chapter Six Consider the following standard reduction potentials in acid solution: 8. The strongest reducing agent among those shown above is a) Fe 3+ b) Fe 2+ c) Br - d) Al 3+ e) Al Determine the equilibrium constant, Keq, at 25 C for the reaction: 2 Br- (aq) + I 2(s) 9. a) 5. 7 10 -19 10. b) 18. 30 c) 1. 7 1054 d) 1. 9 1018 e) 5. 7 10 -55 d) 5. 1 1013 e) None of these Given the following standard reduction potentials, Ag+(aq) + e → Ag(s) Ag. CN(s) + e → Ag(s)+ CN- (aq) E°=0. 80 V E°=-0. 01 V Calculate the solubility product of Ag. CN at 25 C a) 4. 3 10 -14 b) 2. 3 1013 c) 2. 1 10 -14 Br 2(l) + 2 I- (aq)

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C:

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C: 2 Ag+(0. 010 M) + H 2(1 atm) 2 Ag(s) + 2 H+(p. H = 10. 0) a)1. 04 V H 2(g)→ 2 H+ (aq) + 2 e b) 1. 27 V c) 0. 92 V d) 0. 56 V E°= 0. 0 2 e+ 2 Ag+(aq) → 2 Ag (s) E°=0. 80 [H+]=10 -ph H 2(g) + 2 Ag+(aq)→ 2 H+(aq) + 2 Ag(s) E°= 0. 80 , n= 2, T=25+273=298, R=8. 314, F=96500 e) 0. 80 V

Chapter Six Calculate the cell emf for the following reaction at 25 C: 2

Chapter Six Calculate the cell emf for the following reaction at 25 C: 2 Ag+(0. 010 M) + H 2(1 atm) 2 Ag(s) + 2 H+(p. H = 10. 0) 11. a)1. 04 V 12. b) 1. 27 V c) 0. 92 V d) 0. 56 V e) 0. 80 V How many coulombs of charge are required to cause reduction of 0. 20 mole of Cr 3+ to Cr? a) 0. 60 C b) 3. 0 C c) 2. 9 104 C d) 5. 8 104 C e) 9. 65 104 C 3 e +Cr+3 → Cr 3 e ----- 1 mole Cr 3 x 96500 C ---- 1 mol Cr ? C ---- 0. 2 mol Cr Charge = 3 x 96500 x 0. 2 = 5. 8 x 104 C

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C:

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C: 2 Ag+(0. 010 M) + H 2(1 atm) 2 Ag(s) + 2 H+(p. H = 10. 0) a)1. 04 V b) 1. 27 V c) 0. 92 V d) 0. 56 V e) 0. 80 V 12. How many coulombs of charge are required to cause reduction of 0. 20 mole of Cr 3+ to Cr? a) 0. 60 C b) 3. 0 C c) 2. 9 104 C d) 5. 8 104 C e) 9. 65 104 C 13. A current of 0. 80 A was applied to an electrolytic cell containing molten Cd. Cl 2 for 2. 5 hours. Calculate the mass of cadmium metal deposited. a) 3. 2 10 -7 g b) 1. 2 10 -3 g C=Axt = 0. 8 x 2. 5 x 60 = 7200 C c) 4. 2 g d) 8. 4 g Cd → Cd+2 +2 e 1 mole Cd ----- 2 e 1 mol Cd ---- 2 x 96500 C ? mol Cd ---- 7200 e) 16. 8 g

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C:

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C: 2 Ag+(0. 010 M) + H 2(1 atm) 2 Ag(s) + 2 H+(p. H = 10. 0) a)1. 04 V b) 1. 27 V c) 0. 92 V d) 0. 56 V e) 0. 80 V 12. How many coulombs of charge are required to cause reduction of 0. 20 mole of Cr 3+ to Cr? a) 0. 60 C b) 3. 0 C c) 2. 9 104 C d) 5. 8 104 C e) 9. 65 104 C 13. A current of 0. 80 A was applied to an electrolytic cell containing molten Cd. Cl 2 for 2. 5 hours. Calculate the mass of cadmium metal deposited. a) 3. 2 10 -7 g 14. b) 1. 2 10 -3 g c) 4. 2 g d) 8. 4 g e) 16. 8 g A current of 2. 50 A was passed through an electrolytic cell containing molten Ca. Cl 2 for 4. 50 hours. How many moles of calcium metal should be deposited? a) 5. 83 10 -5 mol b) 0. 210 mol c) 0. 420 mol d) 0. 840 mol e) 1. 95 109 mol

Chapter Six 14. A current of 2. 50 A was passed through an electrolytic

Chapter Six 14. A current of 2. 50 A was passed through an electrolytic cell containing molten Ca. Cl 2 for 4. 50 hours. How many moles of calcium metal should be deposited? a) 5. 83 10 -5 mol b) 0. 210 mol C=Axt = 2. 5 x 4. 5 x 60 = 40500 C c) 0. 420 mol d) 0. 840 mol e) 1. 95 109 mol Ca → Ca+2 +2 e 1 mole Ca ----- 2 e 1 mol Ca ---- 2 x 96500 C ? mol Ca ---- 40500

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C:

Chapter Six 11. Calculate the cell emf for the following reaction at 25 C: 2 Ag+(0. 010 M) + H 2(1 atm) 2 Ag(s) + 2 H+(p. H = 10. 0) a)1. 04 V b) 1. 27 V c) 0. 92 V d) 0. 56 V e) 0. 80 V 12. How many coulombs of charge are required to cause reduction of 0. 20 mole of Cr 3+ to Cr? a) 0. 60 C b) 3. 0 C c) 2. 9 104 C d) 5. 8 104 C e) 9. 65 104 C 13. A current of 0. 80 A was applied to an electrolytic cell containing molten Cd. Cl 2 for 2. 5 hours. Calculate the mass of cadmium metal deposited. a) 3. 2 10 -7 g 14. b) 1. 2 10 -3 g c) 4. 2 g d) 8. 4 g e) 16. 8 g A current of 2. 50 A was passed through an electrolytic cell containing molten Ca. Cl 2 for 4. 50 hours. How many moles of calcium metal should be deposited? a) 5. 83 10 -5 mol b) 0. 210 mol c) 0. 420 mol d) 0. 840 mol e) 1. 95 109 mol