Chemistry · Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

NEET (UG) 2023 — Question 69

The right option for the mass of $\mathrm{CO}_{2}$ produced by heating 20 g of $20 \%$ pure limestone is

(Atomic mass of $\mathrm{Ca}=40$ ) $\left[\mathrm{CaCO}_{3} \xrightarrow{1200 \mathrm{~K}} \mathrm{CaO}+\mathrm{CO}_{2}\right]$

Answer: A

\mathrm{CaCO}_3 \xrightarrow{1200 \mathrm{~K}} \mathrm{CaO}+\mathrm{CO}_2

From $100 \mathrm{~g} \mathrm{CaCO}_3 \rightarrow 44 \mathrm{~g} \mathrm{CO}_2$ produced

As $\mathrm{CaCO}_3$ is $20 \%$ pure

So, mass of pure $\mathrm{CaCO}_3=20 \times \frac{20}{100}=4 \mathrm{~g}$

So, $100 \mathrm{~g} \mathrm{CaCO}_3 \rightarrow 44 \mathrm{~g} \mathrm{CO}_2$

\begin{aligned} & 4 \mathrm{~g} \mathrm{CaCO}_3 \rightarrow \frac{44}{100} \times 4 \mathrm{~g} \mathrm{CO}_2 \\ & =1.76 \mathrm{~g} \mathrm{CO}_2 \end{aligned}

Answer key and solution verified before publishing.

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