Question

Copper sulphate solution is electrolysed between two platinum electrodes. a current is passed until 1.6 g of oxygen is liberated at anode. the amount of copper deposited at the cathode during the same period is

Answer 1

Solved Examples on Electrochemistry

Example 1.

Find the charge in coulomb on 1 g-ion of N3-.

Solution:

Charge on one ion of N3-

= 3 × 1.6 × 10-19 coulomb 

Thus, charge on one g-ion of N3-
= 3 × 1.6 10-19 × 6.02 × 1023
= 2.89 × 105  coulomb

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Example 2.

How much charge is required to reduce (a) 1 mole of Al3+ to Al and (b)1 mole  of to Mn2+ ? 

Solution:

(a) 

Answer 2

Copper sulphate solution is electrolysed between two platinum electrodes. A current is passed until 1.6 g of oxygen is liberated at anode. The amount of copper deposited at the cathode during the same period is: (a) 6.36 g (b) 63.68 (c) 12.7 g (d) 3.2 g.