passwella.
Menu

JAMB Chemistry 1997 Question 22

Question 22

Electrolysis

How many faradays of electricity are required to deposit 0.20 mole of nickel, if 0.10 faraday of electricity deposited 2.98 g of nickel during electrolysis of its aqueous solution? [Ni = 58.7, 1F = 96 500 C mol−1]

  1. A.0.20
  2. B.0.30
  3. C.0.40
  4. D.0.50
Show the answer and explanation

Answer: C (0.40)

Explanation

2.98 g of Ni is 2.98/58.7 ≈ 0.05 mol, and it needed 0.10 F (Ni2+ takes 2 F per mole). 0.20 mol therefore needs 0.20 × 2 = 0.40 F.