Question

How many seconds are required to produce 4.00 g of aluminum metal from the electrolysis of molten alcl3 with an electrical current of 12.0 a? a. 1.19 ´ 103 b. 27.0 c. 2.90 ´ 105 d. 9.00 e. 3.57 ´ 103?

Answer 1

The correct answer is e. 3.57×10³
Al³+(aq) + 3e→AL(s)
4.00g of AL=4g/26.98 g/mol= 0.1483 mol
t=znF/1 where t is time in seceonds.
Z= valency number of ions of the substance or electrons which are transferred per ion
F= Faraday's constant
I = electric current in'A'CA  C/s
t=(3×0.1483 mol ×96485 C/mol) /12(C15)
t=3577 second = 3.5 ×10³s