EAMCET Engineering 2008 Solved Paper

Electrolysis of water takes place as follows
H2O⇌‌

H+

‌ cathode ‌

+‌

OH−

‌ anode ‌

At anode
‌OH−

‌ Oxidation ‌

→

‌OH+e−
‌4‌OH→2H2O+O2
At cathode
2H++2e−

‌ Reduction ‌

→

H2
Given, time, ‌‌t=1930 s
Number of moles of hydrogen collected
‌=‌

1120×10−3

22.4

‌ moles ‌
‌=0.05‌ moles ‌
∵1 mole of hydrogen is deposited by =2 moles of electrons
∴0.05 moles of hydrogen will be deposited by
=2×0.05
=0.10 mole of electrons
Charge, Q=nF
=0.1×96500
Charge, Q=it
0.1×96500‌=i×1930
i‌=‌

0.1×96500

1930

‌=5.0A