Question

Function of a buffer is to:
(A) Increase the pH value of the system
(B) Decrease the pH value of the system.
(C) Maintain the pH value of the system
(D) None of these.

Answer 1

Buffer is a chemical solution which resists the changing pH of the solution by adding a small amount of acid or a base. The examples of buffer solutions are phosphate buffer and ammonia buffer. Buffers play an important role to perform a few reactions.

Complete step by step solution:
-A buffer is actually an aqueous solution that consists of a combination of weak acids and their conjugate bases or vice versa.
-The pH of the buffer solution is not going to be altered by the addition of a small amount of an acid or small amount of a base.
-If any reaction is sensitive to the pH of the solution then a buffer is going to be added to complete the particular reaction.
-Means buffer is going to be used to maintain the pH value of the solution.

So, the correct option is (C).

Additional information:
-Ammonia buffer is used to maintain the pH between 8-10, in the determination of hardness of water by using the EDTA method.
-Human blood is also the best example for a buffer.

Note: The function of the buffer is not to keep the pH of the solution to neutral (pH =7). Buffer role is to stop the change in pH of any solution either acidic or basic. There are two types of buffers, they are Acidic buffer and basic buffer.