Elemental calcium is produced by the electrolysis of molten CaCl2.

a) What mass of calcium can be produced by this process if a current of 7.5 * 10^3 A is applied for 48h? Assume that the electrolytic cell is 68% efficient.

b) What is he minimum voltage needed to cause the electrolysis?

6 answers

Coulombs = amperes x seconds
Convert 48 hr to seconds and that x 7500.
That number is close to 173,000 but you should get a better number and that x 7500 = about 1.3E9 C.
96,485 coulombs will plate out 40/2 = 20 g Ca.
So you should be able to plate
20 x 1.3E9/96,485 = g Ca at 100% efficiency. That x 0.68 corrects for not being 100%.

2. Look in the tables and find voltage for Cl and voltage for Ca. The larger is the one you want(ignore the sign).

m=0182.65kg

152.207Kg

i take F =6500 HENCE ANSWER=152.207KG

F=96500

m=183.24kg