An acidic buffer solution can be prepared by mixing the solutions of

Options

A. Sodium chloride and sodium hydroxide
B. Nitric acid and sodium nitrate
C. Ammonium chloride and ammonium hydroxide
D. Sodium acetate and acetic acid

Answer

To determine which pair of solutions can create an acidic buffer, we need to understand the definition of an acidic buffer. An acidic buffer is typically made from a weak acid and the salt of its conjugate base.

Let's analyze the options given:

1. **Sodium chloride (NaCl) and sodium hydroxide (NaOH)**:
- Sodium chloride is a neutral salt, and sodium hydroxide is a strong base.
- There is no weak acid present in this mixture, so it cannot form an acidic buffer.

2. **Nitric acid (HNO3) and sodium nitrate (NaNO3)**:
- Nitric acid is a strong acid, and sodium nitrate is the salt of its conjugate base.
- Since the acid is strong, this combination does not meet the criteria for an acidic buffer, which requires a weak acid.

3. **Ammonium chloride (NH4Cl) and ammonium hydroxide (NH4OH)**:
- Ammonium chloride is a salt, and ammonium hydroxide is a weak base.
- This combination results in a basic buffer, not an acidic buffer, as it consists of a weak base and its conjugate acid.

4. **Sodium acetate (CH3COONa) and acetic acid (CH3COOH)**:
- Acetic acid is a weak acid, and sodium acetate is the salt of its conjugate base.
- This combination perfectly fits the definition of an acidic buffer.

Based on this analysis, the correct answer is:

**Sodium acetate and acetic acid (Option 4)** can be mixed to prepare an acidic buffer solution.