From amongst the following alcohols the one that would react fastest with conc. $\mathrm{HCl}$ and anhydrous…
From amongst the following alcohols the one that would react fastest with conc. $\mathrm{HCl}$ and anhydrous $\mathrm{ZnCl}_2$, is
2-Butanol
2-Methylpropan-2-ol
2-Methylpropanol
1-Butanol
Solution
$3^{\circ}$ alcohols react fastest with $\mathrm{ZnCl}_2 /$ conc. $\mathrm{HCl}$ due to formation of $3^{\circ}$ carbocation and
$\therefore 2-$ methyl propan-2-ol is the only $3^{\circ}$ alcohol