Which of the following solution will have no effect on Ph on dilution ?

Options

A. `0.1 M NH_(4)OH+0.1 M NH_(4)Cl`
B. `0.5MH_(2)CO_(3)+0.5M NaHCO_(3)`
C. `1M CH_(3)COOHN_(4)`
D. `0.1 M CH_(3)COONH_(4)`

Answer

To determine which of the following solutions will have no effect on pH upon dilution, we need to identify buffer solutions among the given options. Buffer solutions are typically composed of a weak acid and its conjugate base or a weak base and its conjugate acid. These solutions resist changes in pH when diluted.

### Step-by-Step Solution:

1. **Identify the Solutions**:
- A) 0.1 M NH4OH + 0.1 M NH4Cl
- B) 0.5 M H2CO3 + 0.5 M NaHCO3
- C) 1 M CH3COONH4
- D) 0.1 M CH3COONH4

2. **Analyze Solution A**:
- NH4OH (ammonium hydroxide) is a weak base, and NH4Cl (ammonium chloride) is the salt of its conjugate acid (NH4+).
- Since it consists of a weak base and its conjugate acid, it forms a buffer solution.
- **Conclusion**: This solution will have no effect on pH upon dilution.

3. **Analyze Solution B**:
- H2CO3 (carbonic acid) is a weak acid, and NaHCO3 (sodium bicarbonate) is its conjugate base (HCO3-).
- This combination also forms a buffer solution.
- **Conclusion**: This solution will also have no effect on pH upon dilution.

4. **Analyze Solution C**:
- CH3COONH4 (ammonium acetate) is a salt formed from acetic acid (weak acid) and ammonia (weak base).
- The presence of both a weak acid and a weak base indicates that this is a buffer solution.
- **Conclusion**: This solution will have no effect on pH upon dilution.

5. **Analyze Solution D**:
- 0.1 M CH3COONH4 is the same as solution C but with a different concentration.
- It still consists of a weak acid (acetic acid) and a weak base (ammonia).
- **Conclusion**: This solution will also have no effect on pH upon dilution.

### Final Conclusion:
All four solutions (A, B, C, and D) are buffer solutions and will have no effect on pH upon dilution.