Question

A mixture on heating gave a gas used as an anaesthetic, 1.1 gm of gas occupies 0.56 L at NTP. Mixture contains:

• A. ${NaNO}_3+{NH}_{4}Cl$
• B. ${NaNO}_2+{NH}_{4}Cl$
• C. ${CaCO}_3+{MgCO}_3$
• D. ${NH}_{4}Cl+{Na}_2{SO}_4$

Answer 1

The correct option is C ${CaCO}_3+{MgCO}_3$

At NTP, 1 mole of any gas occupies a volume of 22.4 L.
Hence, 0.56 L of the gas corresponds to $\frac{0.56}{22.4}=0.025moles$.
1.1 g of gas corresponds to 0.025 moles.
Hence, the molecular weight of gas is $\frac{1.1}{0.025}=44g/mol$.
So, it is carbon dioxide gas which is also used as anaesthetic.
Therefore, the mixture is ${CaCO}_3+{MgCO}_3$.

Thus, the option C is the correct answer.