Assertion (A): When electric current passes through copper sulphate solution, it dissociates
into copper and sulphate ions.
Reason (R): Copper is a good conductor of electricity.

When the current is passed through the copper sulphate solution, it splits into positively charged copper and negatively charged sulphate ions. The copper ions being positive, move toward the negative terminal and the sulphate ions being negative, move toward the positive terminal.

Copper is a good conductor of electricity. Reason is also a true statement, but reason is not the correct explanation for the assertion.