Electrolysis: Practice Questions

During the electrolysis of molten sodium chloride using inert electrodes, which species is produced at the anode?

A constant current of \( 2.0 \text{ A} \) is passed through an aqueous solution of copper(II) sulfate for \( 30 \text{ minutes} \). Which expression correctly calculates the number of moles of copper metal deposited at the cathode?
[Faraday constant, \( F = 96500 \text{ C mol}^{-1} \)]

During the electrolysis of dilute aqueous sulfuric acid, \(\text{H}_2\text{SO}_4\text{(aq)}\), using inert platinum electrodes, what product is formed at the anode?

A steady current of 2.50 A is passed through a solution of copper(II) sulfate for 10.0 minutes. Calculate the total quantity of charge, \( Q \), in coulombs (C) that passed through the circuit during this electrolysis.

During the electrolysis of dilute sulfuric acid using platinum electrodes, a current of \( 0.50 \text{ A} \) is passed for \( 1930 \text{ s} \). Calculate the total volume of gaseous products, in \( \text{cm}^3 \), evolved at both electrodes when measured at r.t.p.
[ \( F = 96500 \text{ C mol}^{-1} \); Molar volume of gas at r.t.p. = \( 24000 \text{ cm}^3 \text{ mol}^{-1} \) ]

An aqueous solution of sodium sulfate, \(Na_2SO_4\), is electrolyzed using inert platinum electrodes as shown in the diagram. A constant current of \(0.500 \text{ A}\) is passed through the solution for \(40.0 \text{ minutes}\).

(a) Using standard electrode potentials, identify the species that is oxidized at the anode and write the balanced half-equation for this process.
(b) Calculate the total charge, \(Q\), that passed through the circuit during the experiment.
(c) Calculate the volume of the gas (in \(\text{cm}^3\)) produced at the anode, measured at \(298 \text{ K}\) and \(10^5 \text{ Pa}\).
[Faraday constant, \(F = 9.65 \times 10^4 \text{ C mol}^{-1}\); Gas constant, \(R = 8.31 \text{ J K}^{-1} \text{ mol}^{-1}\)]