Question

A buffer solution can be prepared from a mixture of:
(This question has multiple correct options. )
A. Sodium acetate and acetic acid in water
B. Sodium acetate and hydrochloric acid in water
C. Ammonia and ammonium chloride in water
D. Ammonia and sodium hydroxide in water.

Answer 1

Hint: Buffer solution is a water solvent based solution which consists of a mixture containing a weak acid and the conjugate base of the weak acid or weak base. They happen to resist a change in pH upon dilution or upon the addition of small amounts of acid/alkali to them.

Complete step by step answer:
Let us know about buffer solutions.
The buffer solution is a solution that can resist changes in Ph even when a small amount of acid or alkali are added to it. Generally when acid is added to buffer, the buffer releases ${ OH }^{ - }$ ions to neutralize the acid which is added similarly, when base is added to buffer the buffer releases ${ H }^{ + }$ ions neutralize the base added to it.

Buffer solution is of two types.
1. Acidic buffer solution:
An acidic buffer solution is nothing but a solution which has a pH less than 7. These solutions are commonly made from a weak acid and one of its salts.

2. Alkaline buffer solution:
An alkaline buffer solution has a pH greater than 7. Alkaline buffer solutions are commonly made from a weak base and one of its salts.

Now, let us consider the question.
As we have already discussed, a buffer solution is formed by a combination of weak acid and salt of weak with a strong base called acidic buffer. For which the example is sodium acetate and acetic acid in water.
Or, it is formed by the combination of weak base and salt or weak base with strong acid called basic buffer. For which the example is ammonium and ammonium chloride in water.

Therefore, option A and C are the required answers.

Note: If you have a very weak acid and one of its salts, this can produce a buffer solution which is actually alkaline. Buffers are important for reactions or processes which need specific pH ranges to happen.