Question

Which of the following will act as buffer?

• A. $H_{2}C{O}_3+N{a}_{2}C{O}_3$
• B. Borax + Boric Acid
• C. $N{H}_{4}Cl+N{H}_{4}OH$
• D. All of these

Answer 1

The correct option is D All of these

A buffer solution is formed by
1) the mixing of a weak base and the salt of its conjugate acid
2) the mixing of a weak acid and the salt of its conjugate base
Carbonic acid is a weak acid, mixed with sodium carbonate, a salt of its conjugate base - the carbonate ion.
Borax is a sodium salt and boric acid is a weak acid.
Ammonium hydroxide is a weak base, ammonium chloride is a salt of the ammonium ion - its conjugate acid.
Hence, all of these is the correct answer.