How much time should a bumper be immersed in Chromium vat?

Question

To save on production costs, most automobile bumpers are never coated with more than 150 g of chromium. Determine how much time a standard bumper should be immersed in a chromium vat? Give your answer to the nearest whole second. 

power supply used in commercial electroplating provides each vat with approximately 1.50 x 10³ A of current.

Answer 1

1.50x10³ amps = 1.50x10³ C/sec

Assuming the plating is tri-valent chromium plating, it will be Cr³⁺ + 3e- ==> Cr(s) and 3 moles of electrons are needed for 1 mole of Cr(s).

150 g Cr x 1 mol/52.0 g = 2.88 moles Cr needed

2.88 moles Cr x 3 e-/mol Cr = 8.65 moles e-

8.65 moles e- x 96,485 C/mol e- = 8.3775x10⁵ C

1.50x10³C/sec (x sec) = 8.3775x10⁵C

x = 586 sec