Problem 73
A Electrolysis of molten NaCl is done in cells operating at \(7.0 \mathrm{V}\) and \(4.0 \times 10^{4} \mathrm{A}\). What mass of \(\mathrm{Na}(\mathrm{s})\) and \(\mathrm{Cl}_{2}(\mathrm{g})\) can be produced in 1 day in such a cell? What is the energy consumption in kilowatt-hours? ( \(1 \mathrm{kWh}=3.6 \times 10^{6} \mathrm{J}\) and \(1 \mathrm{J}=\) \(1 \mathrm{C} \cdot \mathrm{V}\)
Problem 77
Chlorine gas is obtained commercially by electrolysis of brine (a concentrated aqueous solution of NaCl). If the electrolysis cells operate at \(4.6 \mathrm{V}\) and \(3.0 \times 10^{5} \mathrm{A},\) what mass of chlorine can be produced in a 24 -hour day?
Problem 78
Write equations for the half-reactions that occur at the anode and cathode in the electrolysis of molten KBr. What are the products formed at the anode and cathode in the electrolysis of aqueous KBr?
Problem 79
The products formed in the electrolysis of aqueous \(\mathrm{CuSO}_{4}\) are \(\mathrm{Cu}(\mathrm{s})\) and \(\mathrm{O}_{2}(\mathrm{g}) .\) Write equations for the anode and cathode reactions.
Problem 80
Predict the products formed in the electrolysis of an aqueous solution of \(\mathrm{CdSO}_{4}\)
Problem 82
The metallurgy of aluminum involves electrolysis of \(\mathrm{Al}_{2} \mathrm{O}_{3}\) dissolved in molten cryolite \(\left(\mathrm{Na}_{3} \mathrm{AlF}_{6}\right)\) at about \(950^{\circ} \mathrm{C}\). Aluminum metal is produced at the cathode. Predict the anode product and write equations for the reactions occurring at both electrodes.
Problem 86
A voltaic cell set up utilizing the reaction $$ \mathrm{Cu}(\mathrm{s})+2 \mathrm{Ag}^{+}(\mathrm{aq}) \rightarrow \mathrm{Cu}^{2+}(\mathrm{aq})+2 \mathrm{Ag}(\mathrm{s}) $$ has a cell potential of 0.45 V at 298 K. Describe how the potential of this cell will change as the cell is discharged. At what point does the cell potential reach a constant value? Explain your answer.
Problem 87
Two \(\mathrm{Ag}^{+}(\mathrm{aq}) | \mathrm{Ag}(\mathrm{s})\) half-cells are constructed. The first has \(\left|\mathrm{Ag}^{+}\right|=1.0 \mathrm{M},\) the second has \(\left[\mathrm{Ag}^{+}\right]=\) \(1.0 \times 10^{-5} \mathrm{M} .\) When linked together with a salt bridge and external circuit, a cell potential is observed. (This kind of voltaic cell is referred to as a concentration cell.) (a) Draw a picture of this cell, labeling all components. Indicate the cathode and the anode, and indicate in which direction electrons flow in the external circuit. (b) Calculate the cell potential at \(298 \mathrm{K}\)
Problem 92
A Write balanced equations for the follow. ing reduction half-reactions involving organic compounds. (a) \(\mathrm{HCO}_{2} \mathrm{H} \rightarrow \mathrm{CH}_{2} \mathrm{O}\) (acid solution) (b) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CO}_{2} \mathrm{H} \rightarrow \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{3}\) (acid solution) (c) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CHO} \rightarrow\) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}\) (acid solution) (d) \(\mathrm{CH}_{3} \mathrm{OH} \rightarrow \mathrm{CH}_{4}\) (acid solution)
Problem 93
A Balance the following equations involving organic compounds. (a) \(\mathrm{Ag}^{+}(\mathrm{aq})+\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}(\mathrm{aq}) \rightarrow\) \(\mathrm{Ag}(\mathrm{s})+\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CO}_{2} \mathrm{H}(\mathrm{aq})\) (acid solution) (b) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}+\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}(\mathrm{aq}) \rightarrow\) \(\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}(\mathrm{aq})+\mathrm{Cr}^{3+}(\mathrm{aq})\) (acid solution)
