To confirm presence of Hydrogen chloride, a glass rod is dipped in ammonia slthy & held over the mouth of gas jar containing hydrogen chloride gas.

To confirm the presence of hydrogen chloride gas ($\text{HCl}$), a glass rod dipped in concentrated ammonia solution ($\text{NH}_3$) is brought near the gas. The reaction between hydrogen chloride gas and ammonia gas produces dense white fumes of ammonium chloride.
The chemical equation for this reaction is:

The equation written in your notes, $\text{NaCl} + \text{H}_2\text{SO}_4 \rightarrow \text{NaHS}$, is incorrect. The reaction between sodium chloride ($\text{NaCl}$) and concentrated sulfuric acid ($\text{H}_2\text{SO}_4$) is a common method to prepare hydrogen chloride gas.

When sodium chloride reacts with concentrated sulfuric acid, hydrogen chloride gas and sodium bisulfate (or sodium hydrogen sulfate) are produced.
The correct balanced chemical equation is:

The final answer for the corrected chemical equation is $\boxed{\text{NaCl}\text{(s)} + \text{H}_2\text{SO}_4\text{(l)} \rightarrow \text{NaHSO}_4\text{(s)} + \text{HCl}\text{(g)}}$.