Engineering Board Exam Reviewer · Chemistry · hard
How long must a current of 5 A flow to deposit 10 g of silver from a AgNO₃ solution? (Ag = 108, F = 96,485 C/mol)
- 59.6 min
- 29.8 min
- 1787 min
- 0.50 min
Answer
B. 29.8 min
Solution
n(Ag) = 10/108 mol; Ag+ + e- Ag, so Q = nF = 8934 C. t = Q/I = 1787 s = 29.8 min.
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