JEE Main Chemistry question

Buffer solutions have constant acidity and alkalinity because:

(A)They have large excess of H⁺ or OH⁻ ions
(B)They have fixed value of pH
(C)These give unionised acid or base on reaction with added acid or alkaliCorrect
(D)Acids and alkalies in these solutions are shielded from attack by other ions

Answer: (C)

Solution

Added H⁺/OH⁻ is consumed converting the buffer's conjugate component into its weak (largely un-ionised) partner.

Question ID VK-136529