Question

Identify the most stable species in the following set of ions giving reasons:

$A$:


$B$:

Answer 1

$A$:

Stability of carbocations

Carbocation is an electron deficient species. So, electron withdrawing groups further increases the deficiency of electrons and destabilises the carbocation.

Stability order of carbocations :



So, the most stable species will be .

$B$:

Stability of carbanions

Carbanion is an electron rich species. So, any electron withdrawing group will increase the stability of carbanion by withdrawing the electron density.

So, the most stable species will be: