The charring of sugar takes place when treated with concentrated $\mathrm{H}_2 \mathrm{SO}_4$. What is the…
The charring of sugar takes place when treated with concentrated $\mathrm{H}_2 \mathrm{SO}_4$. What is the type of reaction involved in it?
Dehydration reaction
Hydrolysis reaction
Addition Reaction
Disproportionation reaction
Solution
The charring of sugar is its dehydration process. When sugar is treated with conc. $\mathrm{H}_2 \mathrm{SO}_4$, water molecules gets escaped and sugar charcoal is formed. Due to its further reaction with acid, smell of $\mathrm{SO}_2$ is obtained.
$
\begin{array}{rl}
\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}+\left[\mathrm{H}_2 \mathrm{SO}_4\right] & \longrightarrow \\
\text { Sugar } & 12 \mathrm{C}+\left[\mathrm{H}_2 \mathrm{O}+\mathrm{H}_2 \mathrm{SO}_4\right] \\
& \text { Sugar charcoal } \\
\mathrm{C}+2 \mathrm{H}_2 \mathrm{SO}_4 & 2 \mathrm{SO}_2+\mathrm{CO}_2+2 \mathrm{H}_2 \mathrm{O}
\end{array}
$