Chemistry Practice Test: Electrolysis (Questions with Answers and Explanations)

Calculate the mass of copper deposited when a current of 0.5 ampere was passed through a solution of copper (II) chloride for 45 minutes in an electrolytic cell (Cu 64, F = 96500 C mol^-1) (JAMB 2017)

A. 0.300 g      B. 0.250 g      C. 0.224 g      D. 0.448 g

In the electrolytic extraction of calcium from calcium chloride, the cathode is _____

A. iron    B. zinc    C. graphite   D. platinum

The mass of silver deposited when a current of 10 A is passed through a solution of silver salt for 4830 s is ______ [Ag = 108, F = 96500C mol^-1]

A. 54.0 g       B. 27.0 g       C. 13.5 g       D. 108.0 g

2Na₂O_2(s) + 2H₂O_(l)  4NaOH_(aq) + O_2(g)

The substance that is oxidized in the reaction above is _____ (JAMB 2012)

If a given quantity of electricity liberates 0.65 g of Zn²⁺, what amount of Hg^2- would be liberated by the same quantity of current? [Zn = 65, Hg = 201] (JAMB 2008)

A. 1.00 g      B. 2.01 g      C. 4.02 g      D. 8.04 g