State one observation for the following :
Excess ammonium hydroxide solution is added to lead nitrate solution.

Explanation

To solve the question, we need to identify the observation that occurs when excess ammonium hydroxide solution is added to lead nitrate solution. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Identify the Reactants:**
- The reactants in this case are lead nitrate (Pb(NO3)2) and ammonium hydroxide (NH4OH).

2. **Write the Chemical Reaction:**
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