A metallurgist wants to goldplate a thing sheet with the following dimensions: 1.5 in. x 8.5 in. x .0012in. The gold plate must be .0020 in. thick.
a. How many grams of gold (d = 19.3 g/cm^3) are required?
b. How long will it take to plate the sheet from AuCN using a current of 7.00 A? (Assume 100% efficiency.)
Can anyone help me with the above problem. For a. the answer is 16 grams and I am perplexed on how you arrive at the answer. Multiplying 1.5 x 8.5 x.0012 and raising it to the .0020 and multiplying by 2.54cm/1 inch and raising this number to the 3rd power gets you 16 but I am guessing this is the incorrect way to do this.
For b, I did 16 g AuCN x I mol AuCN/197 g Au x 1 mol e-/1 mol AuCN x 9.648 x 10^4/1 mol e- = 7.8 x 10^3/7.00 C/s = 1.1 x 10^3 sec x 1min/60sec = 18 minutes - however the book says the answer is 19minutes.
1 mol e- = 9.648 x 10^4
1A = 1 C/s
I am assuming I did these wrong. Can anyone help me find where I went wrong. Any input would be greatly appreciated. Thank you