oxidation/reduction and electroplating

[Mr Rayon]

okay, yesterday we did an experiment involving oxidation and reduction. It was one of those experiments where you make a circuit and with time notice a build up of metal in one of the two electrodes. Anyway, we used copper for the electrodes. here are the results:

 

Current: 1.0 A

Time: 900 secs

Charge: 900 coloumbs

Initial mass of cathode: 2.58 g

Final mass of cathode: 2.85 g

Mass gain: 0.27 g

 

1) Calculate the quantity of charge, measured in coulombs, required to deposit 63.5 g (1.0 mol) of copper metal.

 

pretty standard question, anyway any help would be appreciated.

both electrodes (anode and cathode) were made of copper. this was dunked into copper sulfate solution for 15 mins.

[cypress]

Since you know the weight of the copper and the charge required to generate that much copper you should be able to determine the total charge required to generate a different quantity by multiplying the known charge by the ratio of the mass right?

[Mr Rayon]

So by solving for x in:

63.5g/0.27g = x/900 C

 

we get the answer?

Does this fraction thing only work for things that are directly proportional (i.e. produces a linear graph when plotted/sketched)?