Explain the following giving suitable reasons: In the manufacture of `H_2SO_4` by contact process:
For the dilution of sulphuric acid, water is not added to the acid but acid is added to water. 

Explanation

### Step-by-Step Solution:

1. **Understanding the Reaction**: Sulfuric acid (H₂SO₄) is a strong acid that has a high affinity for water. When concentrated sulfuric acid comes into contact with water, it undergoes a highly exothermic reaction, meaning it releases a significant amount of heat.

2. **Exothermic Nature of the Reaction**: The reaction between sulfuric acid and water can be represented as:
\[ H₂SO₄ (l) + H₂O (l) \rightarrow H₃O⁺ (aq) + HSO₄⁻ (aq) \]
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