(N/A) $(i)$ Acetic acid reacts with ammonia to form ammonium acetate,which on heating loses water to form acetamide:
$CH_3COOH + NH_3 \rightleftharpoons CH_3COO^-NH_4^+ \xrightarrow{\Delta, -H_2O} CH_3CONH_2$
$(ii)$ Benzoic acid reacts with ammonia to form ammonium benzoate,which on heating loses water to form benzamide:
$C_6H_5COOH + NH_3 \rightleftharpoons C_6H_5COO^-NH_4^+ \xrightarrow{\Delta, -H_2O} C_6H_5CONH_2$
$(iii)$ Phthalic acid reacts with ammonia to form ammonium phthalate,which on heating loses water to form phthalamide,and upon further heating,it loses ammonia to form phthalimide:
$C_6H_4(COOH)_2 + 2NH_3 \rightleftharpoons C_6H_4(COO^-NH_4^+)_2$ $\xrightarrow{\Delta, -2H_2O} C_6H_4(CONH_2)_2$ $\xrightarrow{\Delta, -NH_3} C_6H_4(CO)_2NH$