State one appropriate observation
A few drops of dilute hydrochloric acid are added to silver nitrate solution, followed by addition of ammonium hydroxide solution.

Explanation

### Step-by-Step Solution:

1. **Addition of Dilute Hydrochloric Acid to Silver Nitrate Solution:**
- When a few drops of dilute hydrochloric acid (HCl) are added to silver nitrate (AgNO3) solution, a chemical reaction occurs.
- The reaction can be represented as:
\[ \text{AgNO}_3 (aq) + \text{HCl} (aq) \rightarrow \text{AgCl} (s) + \text{HNO}_3 (aq) \]
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