Question

What happens when a burning splinter is brought near to the mouth of a gas jar containing Hydrogen$\left({\mathrm{H}}_2\right)$ gas?

Answer 1

Laboratory preparation of Hydrogen: Hydrogen is prepared in the laboratory by the action of dilute Hydrochloric acid $\left(\mathrm{HCl}\right)$ or dilute sulphuric acid $\left({\mathrm{H}}_2{\mathrm{SO}}_4\right)$ on granulated Zinc$\left(\mathrm{Zn}\right)$.

Preparation of Hydrogen with Zinc metal: Zinc reacts with dilute Hydrochloric acid to give Zinc chloride and Hydrogen gas.

$$\begin{gathered} \mathrm{Zn}\left(\mathrm{s}\right)+2\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{ZnCl}}_2\left(\mathrm{s}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right) \\ \mathrm{Zinc}\mathrm{dil}.\mathrm{Hydrochloric}\mathrm{Zinc}\mathrm{chlorode}\mathrm{Hydrogen} \\ \mathrm{acid} \end{gathered}$$

Preparation of Hydrogen with Zinc metal: Zinc reacts with dilute Sulphuric acid to give Zinc sulphate and Hydrogen gas.

$$\begin{gathered} \mathrm{Zn}\left(\mathrm{s}\right)+{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)\to {\mathrm{ZnSO}}_4\left(\mathrm{aq}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right) \\ \mathrm{Zinc}\mathrm{dil}.\mathrm{Sulphuric}\mathrm{Zinc}\mathrm{sulphate}\mathrm{Hydrogen} \\ \mathrm{acid} \end{gathered}$$

Test for Hydrogen: Bring a burning splinter near the mouth of the gas jar that formed in the above reaction.

• Being highly combustible, the gas burns with a pop sound, and the splinter gets extinguished.
• Therefore this shows that the gas produced is Hydrogen.