Question

Dry hydrogen when passed over heated metals like Na, K, and Ca, reacts to give their corresponding ______

Answer 1

Dry Hydrogen$\left({\mathrm{H}}_2\right)$:

• Dry hydrogen is simply Hydrogen gas that does not contain water vapour.
• Most metals do not react with Hydrogen gas. but, the metal of group $1$ and $2$ generally reacts with dry Hydrogen to form its hydrides.
• Calcium reacts with dry hydrogen to produce calcium hydride.

$\underset{\mathrm{Sodium}}{2\mathrm{Na}}+\underset{\mathrm{dry}\mathrm{Hydrogen}}{{\mathrm{H}}_2}\to \underset{\mathrm{Sodium}\mathrm{hydride}}{2\mathrm{NaH}}$

• Calcium reacts with dry hydrogen to produce calcium hydride.

$\underset{\mathrm{Calcium}}{\mathrm{Ca}}+\underset{\mathrm{dry}\mathrm{Hydrogen}}{{\mathrm{H}}_2}\to \underset{\mathrm{Calcium}\mathrm{hydride}}{{\mathrm{CaH}}_2}$

So, Dry hydrogen when passed over heated metals like $\mathrm{Na},\mathrm{K},\mathrm{and}\mathrm{Ca}$ reacts to give their corresponding hydrides.