Explanation:
: When ethanol is heated with concentrated sulphuric acid at $443 \mathrm{~K}$, dehydration takes place and ethane is formed. In this reaction concentrated sulphuric acid $\left(\mathrm{H}_2 \mathrm{SO}_4\right)$ acts as a dehydrating agent.
The balanced chemical equation is given by.

Therefore, concentrated sulphuric acid removes water from ethanol, thereby act as a dehydrating agent.