Ch.19 - Electrochemistry

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모든 교과서

Tro 4th Edition

Ch.19 - Electrochemistry

문제 81

A concentration cell consists of two Sn/Sn²⁺ half-cells. The cell has a potential of 0.10 V at 25°C. What is the ratio of the Sn²⁺ concentrations in the two half-cells?

문제 82

A Cu/Cu²⁺ concentration cell has a voltage of 0.22 V at 25 °C. The concentration of Cu²⁺ in one of the half-cells is 1.5×10^–3 M. What is the concentration of Cu²⁺ in the other half-cell? (Assume the concentration in the unknown cell is the lower of the two concentrations.)

문제 83

Determine the optimum mass ratio of Zn to MnO₂ in an alkaline battery.

문제 84

What mass of lead sulfate is formed in a lead–acid storage battery when 1.00 g of Pb undergoes oxidation?

문제 85

Refer to the tabulated values of ∆Gf° in Appendix IIB to calculate E°cell for a fuel cell that employs the reaction between methane gas (CH4) and oxygen to form carbon dioxide and gaseous water.

문제 86

Refer to the tabulated values of ∆G°_f in Appendix IIB to calculate E°_cell for the fuel-cell breathalyzer, which employs the following reaction. ((∆G° for HC₂H₃O₂(g) = -374.2 kJ/mol.)

CH₃CH₂OH(g) + O₂(g) → HC₂H₃O₂(g) + H₂O(g)

문제 87a

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. a. Zn

문제 87b

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. b. Sn

문제 87c

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. c. Mn

문제 88a

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. a. Mg

문제 88b

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. b. Cr

문제 88c

Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. c. Cu

문제 89b

Consider the electrolytic cell: b. Indicate the direction of electron flow.

문제 90

Draw an electrolytic cell in which Mn²⁺ is reduced to Mn and Sn is oxidized to Sn²⁺. Label the anode and cathode, indicate the direction of electron flow, and write an equation for the half-reaction occurring at each electrode. What minimum voltage is necessary to drive the reaction?

문제 91

Write equations for the half-reactions that occur in the electrolysis of molten potassium bromide.

문제 92

What products are obtained in the electrolysis of molten NaI?

문제 93

Write equations for the half-reactions that occur in the electrolysis of a mixture of molten potassium bromide and molten lithium bromide.

문제 94

What products are obtained in the electrolysis of a molten mixture of KI and KBr?

문제 95

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. a. NaBr(aq) b. PbI₂(aq) c. Na₂SO₄(aq)

문제 96a

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. a. Ni(NO₃)₂(aq)

문제 96b,c

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. b. KCl(aq) c. CuBr₂(aq)

문제 97

Make a sketch of an electrolysis cell that electroplates copper onto other metal surfaces. Label the anode and the cathode and indicate the reactions that occur at each.

문제 98

How can one sketch an electrolysis cell that electroplates nickel onto other metal surfaces, labeling the anode and cathode and indicating the reactions that occur at each?

문제 99

Copper can be electroplated at the cathode of an electrolysis cell by the half-reaction: Cu2+(aq) + 2 e- → Cu(s). How much time would it take for 325 mg of copper to be plated at a current of 5.6 A?

문제 100

Silver can be electroplated at the cathode of an electrolysis cell by the half-reaction: Ag⁺(aq) + e^– → Ag(s) What mass of silver would plate onto the cathode if a current of 6.8 A flowed through the cell for 72 min?

문제 101

A major source of sodium metal is the electrolysis of molten sodium chloride. What magnitude of current produces 1.0 kg of sodium metal in 1 hour?

문제 102

What mass of aluminum metal can be produced per hour in the electrolysis of a molten aluminum salt using a current of 25 A?

문제 103

Consider the reaction shown here occurring at 25 °C: A(s) + B2+(aq) → A2+(aq) + B(s). Given that ∆Gr°xn = -14.0 kJ, determine the value of Ec°ell and K for the reaction, and complete the following table for [B2+], [A2+], Q, Ecell, and ∆Grxn with initial values 1.00, 1, 1.0 * 10^-4, 3.54 * 10^-3, and 1.00 * 10^-4 respectively.

문제 104

Consider the reaction shown here occurring at 25°C. Cr(s) + Cd²⁺(aq) → Cr²⁺(aq) + Cd(s) Determine E°_cell, K, and ∆G°_rxn for the reaction and complete the table.

[Cd²⁺] [Cr²⁺] Q E_cell 𝚫G_rxn

1.00 1.00

1.00 1.00 × 10^-5

1.00 × 10^-5 1.00

4.18 × 10^-4 1.00

문제 105

Consider the unbalanced redox reaction: MnO4-(aq) + Zn(s) → Mn2+(aq) + Zn2+(aq). Balance the equation and determine the volume of a 0.500 M KMnO4 solution required to completely react with 2.85 g of Zn.