Calculate the mass of zinc plated on the electrode:
A solution of zinc is elctrolysed for 30 seconds using a current of 1.0 mA calculate the mass of zinc plated on the electrode (suppose 100% current efficiency).
Answer:
Zn2+ + 2e → Zn , molar mass of Zn = 65.38
number of coulombs passed = i × t = 1.0 × 103 A × 30 seconds
m = M r ×Q/96500 × n
= 1×10 -3 × 30 × 65.38/96500 × 2
m = 1.02 × 10-5g