Question

How many grams of cobalt metal will be deposited when a solution of cobalt (II) chloride is electrolyzed with a current of 10 amperes for 109 minutes (1 Faraday = 96,500 C; Atomic mass of Co = 59 u) :

• A. 4
• B. 20
• C. 40
• D. 0.66

Answer 1

Answer: (B)

20

Answer 2

$W =\frac{I t E}{96500}$
$=\frac{10 \times 109 \times 60 \times 59}{96500 \times 2}$
$=19.99 \approx 20$