Question

Four moles of electrons were transferred from anode to cathode in an experiment on electrolysis of water. The total volume of the two gases (dry and S.T.P.) produced will be approximately (in litres)

• A. 22.4
• B. 44.8
• C. 67.2
• D. 89.4

Answer 1

Answer: (C)

67.2

Answer 2

At cathode: $4H^{+} + \underset{(4F)}{4e^{-}} \rightarrow \underset{2moles}{2H_{2}}$ or 2 ×22.4 litres at

S.T.P.

At anode: $2O^{2 -} \rightarrow \underset{1mole}{O_{2}} + \underset{(4F)}{4e^{-}}$ or 22.4 litres at S.T.P.

$\therefore$ Total volume of the two gases produced at S.T.P.$= 2 \times 22.4 + 22.4 = 67.2litres$