Correct statements among the following are

A) At 298 K, p^H of an acidic buffer is always less than 7.

B) Buffer capacity of acidic buffer is maximum when its p^H = p^k_a (of weak acid present in it)

C) Equimolar mixture of NH₄OH and HCl can act like a basic buffer.

D) A basic buffer containing NH₄OH ( p^k_b = 4.8 ) has a p^OH range of 3.8 -5.8.

A) At 298 K, p^H of an acidic buffer can be greater or lesser than or equal to 7.

B) Buffer capacity of acidic buffer is maximum when its p^H = p^k_a , [salt] = [acid]

C) Equimolar mixture of NH₄OH and HCl cannot act like a basic buffer.

     Mixture of excess weak base and limited strong acid can act like a basic buffer.

D) A basic buffer containing NH₄OH ( p^k_b = 4.8 ) has a p^OH range of 3.8 -5.8.

      p^OH range of basic buffer = p^k_b - 1 to p^k_b + 1