A laboratory technician plates nickel metal onto a steel spoon by operating an…
CHEMISTRY · Multi-part · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry
Problem
A laboratory technician plates nickel metal onto a steel spoon by operating an electrolytic cell for 30.0 minutes at a steady current of 2.50 A. The spoon acts as one electrode and is immersed in an aqueous NiSO_{4} solution together with an inert graphite electrode. The cell operates at 25 °C.
(1) Write the oxidation half-reaction and the reduction half-reaction occurring in the cell. Include physical states for all species.
(2) Identify which electrode (spoon or graphite) serves as the anode and which serves as the cathode during electrolysis. Also indicate the sign (positive or negative) of each electrode.
(3) Calculate the mass of Ni (in grams) deposited on the spoon after 30.0 minutes. Use the Faraday constant F=96485C mol−1 and the molar mass of Ni = 58.7 g mol^{-1}.
(4) Describe the direction of electron flow through the external circuit while the plating process is occurring.