Search any question & find its solution
Question:
Answered & Verified by Expert
A solid compound $\mathrm{X}$ on heating gives $\mathrm{CO}_2$ gas and a residue. The residue mixed with water forms Y. On passing an excess of $\mathrm{CO}_2$ through $\mathrm{Y}$ in water, a clear solution $\mathrm{Z}$ is obtained. On boiling $\mathrm{Z}$, compound $\mathrm{X}$ is reformed. The compound $\mathrm{X}$ is:
Options:
Solution:
2144 Upvotes
Verified Answer
The correct answer is:
$\mathrm{CaCO}_3$
$\begin{aligned}
& \mathrm{CaCO}_3 \stackrel{\Delta}{\longrightarrow} \mathrm{CaO}+\mathrm{CO}_2 \uparrow \\
& \mathrm{X} \quad \text { residue } \\
& \mathrm{CaO}+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Ca}(\mathrm{OH})_2 \\
& \mathrm{Y} \\
& \mathrm{Ca}(\mathrm{OH})_2+\mathrm{CO}_2+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Ca}\left(\mathrm{HCO}_3\right)_2 \\
& \mathrm{Z} \\
& \mathrm{Ca}\left(\mathrm{HCO}_3\right)_2 \stackrel{\Delta}{\longrightarrow} \mathrm{CaCO}_3+\mathrm{CO}_2 \uparrow +\mathrm{H}_2 \mathrm{O}
\end{aligned}$
& \mathrm{CaCO}_3 \stackrel{\Delta}{\longrightarrow} \mathrm{CaO}+\mathrm{CO}_2 \uparrow \\
& \mathrm{X} \quad \text { residue } \\
& \mathrm{CaO}+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Ca}(\mathrm{OH})_2 \\
& \mathrm{Y} \\
& \mathrm{Ca}(\mathrm{OH})_2+\mathrm{CO}_2+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{Ca}\left(\mathrm{HCO}_3\right)_2 \\
& \mathrm{Z} \\
& \mathrm{Ca}\left(\mathrm{HCO}_3\right)_2 \stackrel{\Delta}{\longrightarrow} \mathrm{CaCO}_3+\mathrm{CO}_2 \uparrow +\mathrm{H}_2 \mathrm{O}
\end{aligned}$
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.