Question

What is carbocation? Explain with the help of an example and comment on the stability of carbocation.

Answer 1

Carbocation: 

i. A carbon atom having sextet of electrons and a positive charge is called a carbocation.

ii. They are unstable and highly reactive species formed as intermediates in many organic reactions.

iii. In a carbocation, the central carbon atom is sp² hybridized and has trigonal planar geometry.

e. g. In a methyl carbocation C If, the positively charged carbon atom is covalently bonded to three hydrogen atoms. It is planar with H-C-H bond angle of 120°. The unhybridized p_z orbital is vacant and lies perpendicular to the plane containing the three sigma C-H bonds.

iv. Carbocation are classified as primary (1°), secondary (2°) and tertiary (3°). 

v. The stability of carbocations decreases in the order:

Answer 2

A carbocation is a molecule in which a carbon atom has a positive charge and has three bonds. 

Ex:- methanium CH5+ 

The tertiary carbocation is the most stable carbocation bonded with three alkanes