Chemistry HW help

Question

What mass of Co, in grams, will be deposited from a CO2+(aq) solution in an electrolytic cell that operates at 20.0 A for 4.25 hours? (F = 96500 C/mol)

Answer 1

Assuming you mean Co²⁺ ==> Co(s)

Co²⁺(aq) + 2e- ==> Co(s)

20.0 amps = 20 coulombs(C) / sec.

In 4.25 hours, we have 4.25 hrs x 3600 sec / hr = 15,300 sec

20.0 C / sec x 15,300 sec = 306,000 C

moles electrons (e-) = 306,000 C x 1 mol e- / 96,500 C = 3.17 moles e-

moles Co(s) = 3.17 moles e- x 1 mol Co / 2 mols e- = 1.585 mols Co

mass Co = 1.585 mols Co x 58.9 g Co / mol = 93.4 g Co