Consider the following solutions of equal concentrations
`{:(A= NH_(4)Cl,,B = CH_(3)COONa),(C = NH_(4)OH,,D = CH_(3)COOH):}`
A buffer solution can be obtained by mixing equal volumes of

Options

A. C and D
B. A and B
C. A and C
D. C and D

Explanation

To determine which solutions can be mixed to form a buffer solution, we need to understand the requirements for a buffer. A buffer solution is typically made from a weak acid and its conjugate base or a weak base and its conjugate acid.

### Step-by-Step Solution:

1. **Identify the Solutions**: We have the following solutions:
- A: NH₄Cl (Ammonium chloride)
- B: CH₃COONa (Sodium acetate)
- C: NH₄OH (Ammonium hydroxide)
- D: CH₃COOH (Acetic acid)

2. **Determine the Acid-Base Pairs**:
- **For Acetic Buffer**: This requires a weak acid and its conjugate base.
- Weak acid: CH₃COOH (D)
- Conjugate base: CH₃COONa (B)
- **For Basic Buffer**: This requires a weak base and its conjugate acid.
- Weak base: NH₄OH (C)
- Conjugate acid: NH₄Cl (A)

3. **Mixing Solutions**:
- To create an acetic buffer, mix equal volumes of:
- D (CH₃COOH) and B (CH₃COONa)
- To create a basic buffer, mix equal volumes of:
- C (NH₄OH) and A (NH₄Cl)

4. **Conclusion**:
- Therefore, the combinations that can form buffer solutions are:
- For acetic buffer: D (CH₃COOH) + B (CH₃COONa)
- For basic buffer: C (NH₄OH) + A (NH₄Cl)

### Final Answer:
A buffer solution can be obtained by mixing equal volumes of:
- **D (CH₃COOH) and B (CH₃COONa)** for an acetic buffer.
- **C (NH₄OH) and A (NH₄Cl)** for a basic buffer.

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