Among the given cations, the most stable carbonium ion is

MCQ

A
sec-butyl
✓
ter-butyl
C
n-butyl
D
None of these

✓

Answer

Correct option: B.

ter-butyl

b
(b) $\underset{\,\,\,\,\,\,\,\,\,{{3}^{o}}}{\mathop{C{{H}_{3}}-\underset{C{{H}_{3}}}{\overset{\,\,C{{H}_{3}}}{\mathop{\underset{|\,\,\,\,\,}{\overset{|\,\,\,\,}{\mathop{{{C}^{+}}\,}}}\,}}}\,>}}\,\,\underset{\,\,\,\,\,\,\,\,\,\,\,2{}^\circ }{\mathop{C{{H}_{3}}-\underset{C{{H}_{3}}}{\mathop{\underset{|\,\,\,\,\,\,}{\mathop{CH{{_{{}}^{{}}}^{+}}}}\,}}\,>}}\,\,\underset{\begin{matrix}
\begin{matrix}
{} \\
\begin{matrix}
{} \\
{{1}^{o}} \\
\end{matrix} \\
\end{matrix} \\
\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{matrix}}{\mathop{C{{H}_{3}}-CH{{_{2}^{{}}}^{+}}}}\,>\underset{\begin{matrix}
{} \\
\begin{matrix}
{} \\
\begin{smallmatrix}
\text{Methyl } \\
\text{carbocation}
\end{smallmatrix} \\
\end{matrix} \\
\end{matrix}}{\mathop{CH{{_{3}^{{}}}^{+}}\,\,\,\,\,\,\,}}\,$

The higher the number of alkaline groups, the greater the charge is the deflection and hence the more carbonium ion is permanent.