Question

Zinc reacts with NaOH solution to produce.

• A. O₂
• B. H₂
• C. NH₃
• D. NO₂

Answer 1

The correct option is B

H₂

Explanation of the correct option:

Option B: Zinc (Zn) reacts with Sodium hydroxide(NaOH) to form Sodium zincate $\left({\mathrm{Na}}_2\mathrm{Zn}{\mathrm{O}}_2\right)$ with the evolution of hydrogen gas and the reaction takes place at a temperature of ${550}^{\circ }C$. Because some metals react with alkalis to produce salt and H₂ gas. In this reaction, Zinc is metal and NaOH is the alkalis and in the reaction Sodium zincate (salt) and Hydrogen gas is produced. The reaction is given below:

$\underset{\left(\mathrm{Zinc}\right)}{\mathrm{Zn}\left(\mathrm{s}\right)}+\underset{\left(\mathrm{Sodium}\mathrm{hydroxide}\right)}{2\mathrm{NaOH}\left(\mathrm{aq}\right)}\to \underset{\left(\mathrm{Sodium}\mathrm{Zincate}\right)}{2{\mathrm{Na}}_2{\mathrm{ZnO}}_2\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Hydrogen}\right)}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$

Final Answer: Zinc(Zn) reacts with Sodium hydroxide(NaOH) to form sodium zincate with the evolution of hydrogen gas.