Question

In which of the following aqueous solutions of salt, is pH independent of the concentration of the salt?

• A. Ammonium chloride
• B. Ferric chloride
• C. Ammonium acetate
• D. Sodium acetate
• E. Ammonium sulphate

Hint:

Buffer solutions resist changes in pH upon dilution or the addition of small amounts of acids or bases.

Answer 1

The Correct Option is C

Step 1: Ammonium acetate (\(CH_3COONH_4\)) is a salt derived from a weak acid (acetic acid) and a weak base (ammonia). 
Step 2: When dissolved in water, it completely dissociates into \(CH_3COO^-\) and \(NH_4^+\). 
Step 3: Both the anion and the cation can react with water, but their effects on pH largely cancel each other out, resulting in a solution that acts as a buffer. 
Step 4: Therefore, the pH of ammonium acetate solutions is relatively independent of its concentration compared to salts that yield ions from strong acids or bases.