Question

Ortho hydroxy benzoic acid more acidic than para hydroxybenzoic acid

Answer 1

Ortho hydroxy benzoic acid is more acidic than para hydroxybenzoic acid. Ortho position is the second position of the benzene ring while para position is the second position of the benzene ring. In other words, Ortho benzoic acid can also be referred to as 2-hydrobenzoic acid and para hydroxy benzoic acid as 4-hydroxybenzoic acid.

so to answer your question, ortho hydroxy benzoic acid is more acidic because in the ortho isomer, strong hydrogen bridge will be formed  between the phenolic -OH- and the carboxylate ion and this will tend to stabilize the conjugate crboxylate base hence increasing the acidity.

Answer 2

Ortho hydroxy benzoic acid is more acidic than para hydroxybenzoic acid. Ortho position is the second position of the benzene ring while para position is the second position of the benzene ring. In other words, Ortho benzoic acid can also be referred to as 2-hydrobenzoic acid and para hydroxy benzoic acid as 4-hydroxybenzoic acid.

so to answer your question, ortho hydroxy benzoic acid is more acidic because in the ortho isomer, strong hydrogen bridge will be formed  between the phenolic -OH- and the carboxylate ion and this will tend to stabilize the conjugate crboxylate base hence increasing the acidity.