Given below are the steps for extraction of copper from its ore. Write the reaction involved. 
(i) Roasting of copper (I) sulphide.
(ii) Reduction of copper (I) oxide with copper (I) sulphide.
(iii) Electrolytic refining
(b) Draw a neat and well labelled diagram for electrolytic refining of copper.

Explanation

To extract copper from its ore, the following steps are involved along with the respective reactions:

### Step 1: Roasting of Copper (I) Sulphide
- **Reaction**: When copper (I) sulphide (Cu₂S) is roasted in the presence of oxygen (O₂), it undergoes oxidation to form copper (I) oxide (Cu₂O) and sulfur dioxide (SO₂).

\[ 2 \text{Cu}_2\text{S} + 3 \text{O}_2 \rightarrow 2 \text{Cu}_2\text{O} + 2 \text{SO}_2 \]
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