Which of the two structures (A) and (B) given below is more stabilised by resonance ? Explain
`underset((A))(CH_(3)COOH)" "` and `" "underset((B))(CH_(3)COO^(-))`

Explanation

Resonance structures of compound (A) and (B) are given below :

Resonance structure (II) carries separation of +ve and -ve charges and hence it is less stable than structure (I). AS a result, contribution of structure (II) towards resonance hybrid of compound A is less than that of structure (I).
In contrast, both the resonance of compound (B), i.e., III and IV are of equal energy and hence contribute equally towards the resonance hybrid of structure (B). Thus, structure (B) is more stable than structure (A).