Chemistry Question on Stoichiometry and Stoichiometric Calculations

Question

The decomposition of a certain mass of $CaCO_3$ gave $11.2\, dm^3$ of $CO_2$ gas at $STP$ . The mass of $KOH$ required to completely neutralise the gas is

Answer 1

Solution

Weight of $11.2 \,dm ^{3}$ of $CO _{2}$ gas at $STP =44 / 2$
$\underset{56\,g}{KOH}+\underset{44\,g}{CO_2}\to KHCO_3$

KOH required for complete neutralisation requires of $22 \,g$ of $CO _{2}$ is

$=\frac{56}{44} \times 22=28 \,g$