Ortho effect is a special type of effect that is shown by d-substituents, but it is not necessarily just a steric effect.This ortho-effect opertes with the benzoic acid.Irrespective of the polar types nearly all o-substitued benzoic acid are stronger than unsubstituted beznoic acid.Benzoic acid is a resonance hybrid and so the carboxyl group is coplanar with the ring.An o-substituent tends to prevent this coplanarity . Ortho effect also opertes in substituted anilines where as ortho substituent has base weakening effect. What is the order of acidity of following compounds :

Ortho effect is a special type of effect that is shown by d-substituen

1.	Ortho effect is a special type of effect that is shown by d-substituents, but it is not necessarily just a steric effect.This ortho-effect opertes with the benzoic acid.Irrespective of the polar types nearly all o-substitued benzoic acid are stronger than unsubstituted beznoic acid.Benzoic acid is a resonance hybrid and so the carboxyl group is coplanar with the ring.An o-substituent tends to prevent this coplanarity . Ortho effect also opertes in substituted anilines where as ortho substituent has base weakening effect. What is the order of acidity of following compounds :
Answer» IgtIVgtIIIgtII IgtIIIgtIVgtII IVgtIgtIIIgtII IIIgtIVgtIgtII Solution :(i)Is STRONGEST due to intramolecular bond formation in conjugate BASE. (iv)Comes NEXT due to intramolecular H bonding with OH GROUP. (iii)Comes next due to ortho EFFECT.