A current of 4.91 A is passed through a Ni(NO3)2 solution. How long, in hours, would this current have to be applied to plate out 9.40 g of nickel? time required: h

Answer 1

Ni²⁺ + 2e- ==> Ni(s)

4.91 A = 4.91 Coulombs / second = 4.91 C/s

atomic mass Ni = 58.7 g / mole

9.40 g Ni x 1 mol Ni / 58.7 g = 0.160 moles of Ni

0.160 mols Ni x 2 mol e- / mol Ni = 0.320 mols electrons needed

0.320 mols e- x 96485 C / mol e- = 30,875 C

Converting this to seconds, we have ...

30,875 C x 1 s / 4.91 C = 6288 s

Converting to hours, we have ...

6288 s x 1 hr / 3600 s = 1.75 hrs