Question

Identify X and Y in the following chemical reaction.

$\text{NaOH(aq)}+\text{X}\to {\text{Na}}_2{\text{ZnO}}_2\text{(aq)}+\text{Y}$

• A. X is Na and Y is hydrogen.
• B. X is Cu and Y is water.
• C. X is Zn and Y is water.
• D. X is Zn and Y is hydrogen.

Answer 1

The correct option is D X is Zn and Y is hydrogen.

Amphoteric metals are ones that can react with both acids and bases. Examples include: aluminium, tin, lead, zinc. When bases like $\text{NaOH}$ or $\text{KOH}$ react with amphoteric metals, salt and hydrogen gas are formed as products.
Here, sodium hydroxide on reaction with zinc gives sodium zincate and hydrogen gas. The reaction occurs as follows:

$\text{2NaOH(aq)}+\text{Zn(s)}\to {\text{Na}}_2{\text{ZnO}}_2\text{(aq)}+{\text{H}}_2\text{(g)}$