Question

What mass of cu(s) is electroplated by running 26.5 a of current through a cu2+(aq) solution for 4.00 h?

Answer 1

T = 14400 s 
26.5 x 14400=381600 C 
381600/96500=3.95 Faradays 
Cu2+ + 2e- = Cu 
3.95 faradays ( 1 mol/ 2 Faradays) = 1.97
mass = 1.97 x 63.55 g/mol=125 g 

moles Au = 33.1 / 196.967 g/mol=0.168 
Au+ + 1e- = Au 
0.168 ( 1 Faraday/ 1mol)= 0.168 Faraday 
0.168 x 96500=16217 Coulombs 
16217 / 5.00=3243 s => 54 min