Question 25
ElectrolysisWhat quantity of aluminium is deposited when a current of 10A is passed through a solution of an aluminium salt for 1930s? [Al = 27, F = 96 500 C mol−1]
- A.0.2 g
- B.1.8 g
- C.5.4 g
- D.14.2 g
Show the answer and explanation
Answer: B (1.8 g)
Explanation
Q = 10 × 1930 = 19 300 C = 0.2 F. Al3+ needs 3 F per mole, so 0.2/3 mol × 27 = 1.8 g.