Question

If 96500 coulombs of electricity liberates one gram equivalent of any substance, the time taken for a current of 0.15 amperes to deposite 20mg of copper from a solution of copper sulphate is (Chemical equivalent of copper = 32)

• A. 5 min 20 sec
• B. 6 min 42 sec
• C. 4 min 40 sec
• D. 5 min 50 sec

Answer 1

Answer: (B)

6 min 42 sec

Answer 2

$m = Zit$ ⇒ $20 \times 10^{- 3} = \left( \frac{32}{96500} \right) \times 0.15 \times t$

$= 6.7min = 6min.42sec$