1)Is resonance stabilisation in benzoic acid any different from that of an alkanoic acid, after the removal of H ion?
2)Can benzoic acid support negative charge on both the oxygens simultaneously?
3)Which of the two acids is more acidic?
- The difference in resonance stabilisation between the aromatic acids and aliphatic acids is due to what happens within the benzene ring.
- If you imply benzoate ion then yes, it can be visualised as \(-\delta\) & \(-\delta\) or -1/2 & -1/2 but it is more about delocalisation than accumulation. Same is the case with aliphatic acids.
- It is not specified which alkanoic acid is being referred to. However, Benzoic acid is more acidic than ethanoic acid. The -COOH group in benzoic acid is connected to sp2 hybridised carbon having 33.33% s character in comparison to sp3 hybridised carbon connected to -COOH group in ethanoic acid having 25% s character. sp2 therefore has more electron withdrawing effect than sp3. If electrons are withdrawn more in the ion formed after deprotonation, it is good for the stability of the ion as the probability of recombination with H+ floating around in the solution becomes less (electromagnetic force weakens). Note that it is a game of equilibrium.
Thank You Sir.