Question

32.5 g of zinc (At. mass 65) will completely react with dilute sulphuric acid to give

• A. 1 mol of $H_2$
• B. 1/2 mol of $H_2$
• C. 2/3 mol of $H_2$
• D. Both 2/3 mol of 02 and 1/2 mol of $H_2$

Answer 1

The Correct Option is B

$\underset{\text{65 g}}{Zn}+H_{2}SO_{4} \to \underset{\text{1 mol}}{ZnSO_{4}}+H_{2}$ $\because$ $32\,g$ of $Zn$ wiil produce $H_{2}=1/2\,mol$

Answer 2

Given:
Mass of zinc (Zn) = 32.5 g
Atomic mass of zinc (Zn) = 65 g/mol

Calculate moles of zinc:
\(\text{Moles of Zn} = \frac{\text{Mass}}{\text{Molar mass}} = \frac{32.5 \text{ g}}{65 \text{ g/mol}} = 0.5 \text{ mol}\)

Determine moles of hydrogen gas (H₂) produced:
According to the balanced chemical equation:
\(\text{Zn} + \text{H}_2\text{SO}_4 \rightarrow \text{ZnSO}_4 + \text{H}_2\)
1 mole of zinc produces 1 mole of hydrogen gas.
Therefore, 0.5 moles of zinc will produce:
\(\text{Moles of } H_2 = 0.5 \text{ mol}\)\(=\frac{1}{2}\) mol of \(H_2\)

So, the correct option is (B): \(\frac{1}{2}\) mol of \(H_2\).