Dissociation of `NH_(4)OH` is decreased in presence of :-

Options

A. `CH_(3)COOH`
B. KOH
C. `HNO_(3)`
D. None of these

Answer

To solve the question regarding the dissociation of \( NH_4OH \) (ammonium hydroxide) and how it is affected by the presence of other compounds, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Dissociation of Ammonium Hydroxide:**
- Ammonium hydroxide dissociates in water to form ammonium ions (\( NH_4^+ \)) and hydroxide ions (\( OH^- \)).
- The dissociation can be represented as:
\[ NH_4OH \rightleftharpoons NH_4^+ + OH^- \]

2. **Identifying the Common Ion Effect:**
- The common ion effect states that the dissociation of a weak electrolyte is suppressed when a strong electrolyte that provides a common ion is added to the solution.
- In this case, we need to identify which of the given compounds produces either \( NH_4^+ \) or \( OH^- \) ions.

3. **Analyzing Each Option:**
- **Option A: Acetic Acid (\( CH_3COOH \))**
- Dissociates to give \( CH_3COO^- \) and \( H^+ \).
- Does not produce \( NH_4^+ \) or \( OH^- \).
- **Effect:** No common ion effect; dissociation of \( NH_4OH \) is not decreased.

- **Option B: Potassium Hydroxide (\( KOH \))**
- Dissociates to give \( K^+ \) and \( OH^- \).
- Produces \( OH^- \), which is a common ion with \( NH_4OH \).
- **Effect:** The presence of \( OH^- \) will decrease the dissociation of \( NH_4OH \) due to the common ion effect.

- **Option C: Nitric Acid (\( HNO_3 \))**
- Dissociates to give \( H^+ \) and \( NO_3^- \).
- Does not produce \( NH_4^+ \) or \( OH^- \).
- **Effect:** No common ion effect; dissociation of \( NH_4OH \) is not decreased.

- **Option D: Sodium Chloride (\( NaCl \))**
- Dissociates to give \( Na^+ \) and \( Cl^- \).
- Does not produce \( NH_4^+ \) or \( OH^- \).
- **Effect:** No common ion effect; dissociation of \( NH_4OH \) is not decreased.

4. **Conclusion:**
- The only compound that decreases the dissociation of \( NH_4OH \) is **Potassium Hydroxide** because it provides the common ion \( OH^- \).

### Final Answer:
The dissociation of \( NH_4OH \) is decreased in the presence of **Potassium Hydroxide (KOH)**.

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