Identifying the Ideal Buffer Solution- Which of the Following Options Meets the Criteria-

Which of the following solutions is a buffer?

In chemistry, a buffer solution is a mixture that helps maintain a relatively constant pH when small amounts of acid or base are added. Buffers are crucial in various biological and chemical processes, as they prevent significant changes in pH that could disrupt enzyme activity or other biochemical reactions. Determining which of the following solutions is a buffer requires an understanding of the components and their ability to resist pH changes.

A. 0.1 M HCl
B. 0.1 M NaOH
C. 0.1 M CH3COOH and 0.1 M CH3COONa
D. 0.1 M NaCl

Let’s analyze each option to determine which one qualifies as a buffer.

A. 0.1 M HCl is a strong acid. When added to a solution, it will dissociate completely, leading to a significant decrease in pH. Therefore, it is not a buffer.

B. 0.1 M NaOH is a strong base. Similar to HCl, it will dissociate completely, resulting in a significant increase in pH. Hence, it is not a buffer either.

C. 0.1 M CH3COOH and 0.1 M CH3COONa is a classic example of a buffer solution. CH3COOH is a weak acid, and CH3COONa is its conjugate base. When these two substances are mixed, they form a buffer system that can resist pH changes. The weak acid can donate a proton (H+) to neutralize a base, while the conjugate base can accept a proton from an acid. This dynamic equilibrium allows the buffer to maintain a relatively constant pH.

D. 0.1 M NaCl is a salt formed from the reaction of a strong acid (HCl) and a strong base (NaOH). It does not have the ability to resist pH changes, so it is not a buffer.

In conclusion, the solution that is a buffer is:

C. 0.1 M CH3COOH and 0.1 M CH3COONa

This buffer system is widely used in various applications, including biological research, pharmaceuticals, and food preservation.