Engineering Board Exam Reviewer · Chemistry · hard
How many grams of copper are deposited from a CuSO₄ solution by a current of 2 A flowing for 1 hour? (Cu = 63.5, F = 96,485 C/mol)
- 4.739 g
- 2.369 g
- 0.0395 g
- 1.580 g
Answer
B. 2.369 g
Solution
Q = It = 2(3600) = 7200 C. n(e-) = 7200/96,485 = 0.0746 mol. Cu2+ needs 2e-: m = (0.0746/2)(63.5) = 2.369 g.
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