1-Butanol is heated with concentrated sulphuric acid at 443 k.

Explanation

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactant is 1-butanol (C4H10O) and concentrated sulfuric acid (H2SO4).

2. **Draw the Structure of 1-Butanol**: The structure of 1-butanol is CH3-CH2-CH2-CH2-OH.

3. **Protonation of Alcohol**: When 1-butanol is heated with concentrated sulfuric acid, the hydroxyl group (OH) of 1-butanol gets protonated by H2SO4, forming a better leaving group (water). The reaction can be represented as:
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