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Question
A current strength of 3.86 A was passed through molten Calcium oxide for 41minutes and 40 seconds. The mass of Calcium in grams deposited at the cathode is (atomic mass of Ca is 40g/mol and 1F = 96500 C).
Options
4
2
8
6
Solution
2
Explanation:
m = ZIt
41 min 40 sec = 2500 seconds
= `(40 xx 3.86 xx 2500)/(2 xx 96500)`
Z = `"m"/("n" xx 96500)`
= `40/(2 xx 96500)`
= 2g
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