Plastic items can be chrome plated by coating them with a thin layer of graphite paste, placing them in a bath of aqueous chromium(III) sulfate and galvanizing. a) Suggest a reason why the article is coated with graphite first.
b) what substance could be used for the other electrode in the electroplating cell/
c) Draw an electrical circuit diagram for electroplating.
d) If a current of 0.5 A passed through the cell for 300 seconds, what would be the increase in mass due to the chrome plating?
e) why is it not possible to coat articles with zinc by this method? The plastic item should be one of the electrodes but it does not conduct electricity. Therefore, the graphite coating serves this purpose.
I think a graphite rod or a carbon rod would serve as another electrode.
amperes x seconds = coulombs
0.5A x 300s = 150 coulombs,
96,485 coulombs will deposit 52.0/3 = 17.33 g Cr.
g Cr clad = 17.33 x 150/96,485 = ? gCr. Graphite is an internal electrode that is not involved in reactions