Biology Forums - Study Force

Electroplating is a widely used process. One of the most popular electroplating processes involves the plating of two metals, nickel and chromium, in separate vats. Nickel is plated first because it adheres better to iron, then the object is moved to a second vat where a layer of chromium is plated. The half-reactions occurring in each vat are shown below:

Plating of Nickel        Ni2+(aq) + 2 e- → Ni(s)

Plating of Chromium   Cr2O72-(aq) + 14 H+(aq) + 12 e- → 2 Cr(s) + 7 H2O(l)

To save on production costs, most automobile bumpers are never coated with more than 200 g of chromium. Determine how much time a standard bumper should be immersed in a chromium vat.

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