Two electrolytic cells—Cell A containing NiCl (aq) and Cell B containing FeCl…
CHEMISTRY · Multi-part · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry
Problem
Two electrolytic cells—Cell A containing NiCl2(aq) and Cell B containing FeCl3(aq)—are initially connected in series to a direct-current supply that delivers a steady current of 4.00A. After exactly 12.0min the wiring is changed so that the same two cells operate in parallel across the same supply for an additional 12.0min. In the parallel configuration the effective resistances are 1.50Ω for Cell A and 3.00Ω for Cell B. Assume 100 % current efficiency and ignore any transients during switching.
(a) Calculate the total charge that passes through the circuit during the initial 12.0min series operation.
(b) Determine the masses of nickel and iron deposited, respectively, during the series period.
(c) For the parallel period, calculate the current that flows through each cell.
(d) Determine the additional masses of nickel and iron deposited, respectively, during the parallel period.
(e) Calculate the total mass of nickel and the total mass of iron present on the cathodes after the full 24.0min experiment.