Question

Which of the following statements is wrong?

• A. A tertiary free radical is more stable than a secondary free radical.
• B. A secondary free radical is more stable than a primary free radical.
• C. A tertiary carbocation is more stable is more stable than secondary carbocation.
• D. A primary carbocation is more stable than secondary carbocation

Answer 1

The correct option is D A primary carbocation is more stable than secondary carbocation

A tertiary carbocation is more stable than secondary carbocation, which is more stable than primary carbocation. In tertiary carbocation, three alkyl groups stabilise the positive charge while in secondary and primary carbocation two and one alkyl groups stabilise the positive charge respectively. Therefore stability order is as follows:

Tertiary > Secondary > Primary

In case of free radical, stability order is as follows:

Tertiary > Secondary > Primary