1. Moles of zinc taken

Given mass of zinc $= 5\,\text{g}$.

Using molar mass of zinc $\approx 65\,\text{g mol}^{-1}$,

$n(\text{Zn}) = \frac{5}{65} = \frac{1}{13}\,\text{mol}$

2. Reaction with dilute hydrochloric acid

Zinc reacts with dilute HCl as:

$\text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2$

From the equation,

$1\,\text{mol Zn} \rightarrow 1\,\text{mol H}_2$

So, $\frac{1}{13}$ mol Zn will produce

$\frac{1}{13}\,\text{mol H}_2$

3. Reaction with aqueous sodium hydroxide

Zinc is amphoteric and reacts with aqueous NaOH as:

$\text{Zn} + 2\text{NaOH} + 2\text{H}_2\text{O} \rightarrow \text{Na}_2[\text{Zn(OH)}_4] + \text{H}_2$

(or equivalently written via sodium zincate formation)

Again, from the equation,

$1\,\text{mol Zn} \rightarrow 1\,\text{mol H}_2$

So, $\frac{1}{13}$ mol Zn will also produce

$\frac{1}{13}\,\text{mol H}_2$

4. Ratio of volumes of hydrogen evolved

At the same temperature and pressure, gas volume is proportional to number of moles.

Thus,

$V_{\text{H}_2}(\text{with HCl}) : V_{\text{H}_2}(\text{with NaOH}) = \frac{1}{13} : \frac{1}{13} = 1:1$

5. Option check

• A: $1:2$ ❌
• B: $1:1$ ✅
• C: $1:4$ ❌
• D: $2:1$ ❌

Therefore, the correct answer is B.