Question

Metals like magnesium, zink and iron on heating react with steam to form hydrogen gas and their respective

• A. hydroxides
• B. oxides
• C. hydrides
• D. none of these

Answer 1

The correct option is B

oxides

The explanation for the right answer:

Option B: oxides

• Some moderate reactive metals like $\mathrm{Magnesium}\left(\mathrm{Mg}\right)$ and $\mathrm{Zinc}\left(\mathrm{Zn}\right)$ react with steam to liberate $\mathrm{Hydrogen}\mathrm{gas}\left({\mathrm{H}}_2\right)$ metallic oxide.
• So, option B is the correct answer.

The explanations for the wrong answers:

Option A: hydroxide

• Some moderate reactive metals like $\mathrm{Magnesium}\left(\mathrm{Mg}\right)$ and $\mathrm{Zinc}\left(\mathrm{Zn}\right)$ react with steam to liberate $\mathrm{Hydrogen}\mathrm{gas}\left({\mathrm{H}}_2\right)$ metallic oxide, not hydroxides.
• So, option A is the wrong answer.

Option C: hydrides

• Metals with $\mathrm{Hydrogen}$ as an anion $\left({\mathrm{H}}^{-}\right)$ and metal as cation $\left({\mathrm{M}}^{+}\right)$called metal hydrides.
• So, option C is the wrong answer.

Conclusion:

So, metals like $\mathrm{Magnesium}\left(\mathrm{Mg}\right)$ and $\mathrm{Zink}\left(\mathrm{Zn}\right)$ react with steam to liberate $\mathrm{Hydrogen}\mathrm{gas}\left({\mathrm{H}}_2\right)$ and respective oxides.

Therefore, Option B is the correct answer.