(a) Suggest a solvent in which aniline acts as strong base.
(b) Write equation for the auto-ionisation of (i) `HCOOH`, (ii) `NH_(3)` .
(c ) `[A] (H_(2)O)_(6)]^(3+)` is acid or base and write its conjugate paranter and reaction.
(d) Write the order of acidic nature of `HCI, HCOOH` and `CH_(3)COOH` in (i) `H_(2)O`, (ii) liq. `NH_(3)`.

Explanation

(a) Aniline (a weak base) acts as strong base in liquid acetic acid.
(b) (i) `2HCOOH hArr HCOO^(-)+HCOOH_(2)^(+)`
(ii) `2NH_(3) hArr NH_(4)^(+)+NH_(2)^(-)`
(c ) `[A](H_(2)O)_(6)]^(3+)` is acid:
`underset("Conjugate base")([A](H_(20))_(6)]^(3+)+ H_(2)O hArr [Al(H_(2)O)_(5)OH]^(2+)+H_(3)O^(+)`
(d) (i) In `H_(2)O :HCIgtHCOOHgtCH_(3)COOH`
(ii) `"In liq". NH_(3)`: All are strong acids.