What mass of magnesium would be obtained by passing a current of 2 amperes for 2 hours 30 mins, through molten magnesium chloride?
[1 faraday = 96500C, Mg = 24]

A.

1.12g

B.

4.48g

C.

1.80g

D.

2.00g

Correct answer is D

Given  Data:

Time (T) = 2hrs 30mins 

where 2hrs =120mins

2hrs & 30mins = (120 + 30)mins = 150mins

150mins to Seconds = 150 x60 = 9,000s

Q = I x T

2 x 9,000 =18,000

where mg has valency of +2

So 2 x 96500 will discharge 24g of mg

and 18,000 will discharge xg of mg

2 x 96500 =24

18,000 =x

x = \(\frac{24 \times 18,000}{2 x 96500}\)

≈ 2.00g