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]
- 1.12g
- 4.48g
- 1.80g
-
2.00g
The correct answer is: D
Explanation
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
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