Which of the following can act as buffer ?

Options

A. `NaCl+NaOH`
B. Borax+ Boric acid
C. `NaH_(2)PO_(4)+Na_(2)HPO_(4)`
D. `NH_(4)Cl+NH_(4)OH`

Answer

B:C:D

Explanation

(b) and (d) are correct because they have common ion and one of them is weak electrolyte.
(a) is not correct because NaCl and NaOH both are strong electrolytes and will not have common ion effect.
© isnot correct because both are salt and strong electrolytes., cannot from buffer solution.