Electrolysis Creating Bismuth

Question

The electrolysis of BiO+ produces pure bismuth. How long would it take to produce 10.0 g Bi by the electrolysis of a BiO+ solution using a current of 25.0 A?

Answer 1

In BiO⁺, Bi has an oxidation number of 3+, so it’ll take 3 moles of electrons per mole of Bi.

10.0 g Bi x 1 mole/209g = 0.0478 moles Bi

0.0478 moles Bi x 3 moles electrons/mol Bi = 0.1434 moles electrons

0.1434 mol e^- x 96,485 C/mole = 13836 Coulombs

1 C = 1 amp/sec

13836 C = 25 A x time

time = 553 seconds = 9.2 minutes