In each of the following sections four compounds are listed. (Decreasing order of acidic strength, 1 is strongest & 4 is weakest).

Answer

`(a) 3 2 1 4; (b) 2 1 4 3; (c) 3 1 2 4; (d) 3 4 1 2`

Explanation

(A) Acidic strength -I, - M `prop` stability of conjugate base.

Acidic strength `prop(1)/("distance of group from reaction centre")`
(B) Acidic strength `prop` of -1 groups `prop(1)/(+I)`
`a-3,2,1,4, b-2,1,4,3, c-2,1,3,4, d-2,4,3,1`