Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at STP from the reaction of 11.5 g of zinc with excess HCl is L (Nearest integer)
(Given: Molar mass of Zn is 65.4 g mol$$^{-1}$$ and Molar volume of H$$_2$$ at STP = 22.7 L)

The balanced equation for the reaction:

$$ Zn + 2HCl \rightarrow ZnCl_2 + H_2 $$

Moles of zinc:

$$ n_{Zn} = \frac{11.5}{65.4} = 0.1758 \text{ mol} $$

From the stoichiometry, 1 mole of Zn produces 1 mole of H$$_2$$:

$$ n_{H_2} = 0.1758 \text{ mol} $$

Volume of H$$_2$$ at STP:

$$ V = n \times V_m = 0.1758 \times 22.7 = 3.99 \approx 4 \text{ L} $$