Question

The geometry of a carbocation is

• A. linear
• B. planar
• C. tetrahedral
• D. octahedral

Answer 1

The correct option is B

planar

Explanation for correct option

(B) planar

• A species having a carbon atom possessing a sextet of electrons and a positive charge is called a carbocation.
• ${\mathrm{CH}}_3^{+}$ is $s{p}^2$ hybridized. It is the mixture of one s-orbital and two p-orbitals.
• Hence, the geometry of carbocation is trigonal planar as it has three sigma bonds.
• All the $\mathrm{H}$and $\mathrm{C}$ lie in one plane.
• 

So, the geometry of carbocation is planar.

Explanation for incorrect option

(A) Linear

An example of a linear molecule is ${\mathrm{CO}}_2$.

Hybridization of the linear molecule is sp.

(C)Tetrahedral

An example of tetrahedral is ${\mathrm{CH}}_4$.

Hybridization of the tetrahedral molecule is $s{p}^3$.

(D) octahedral

An example of an octahedral is ${\mathrm{SF}}_6$.

The hybridization of an octahedral molecule is sp³d² (or d²sp³).

The geometry of carbocation is planar. Hence, options (A), (C), and (D) are incorrect.

Hence, the correct option is (B). The geometry of carbocation is planar.