A beaker contains a solution of substance'A' precipitation of substance 'A' takes place when small amount of 'A' is added to the solution. The solution is………

Options

A. saturated
B. supersaturated
C. unsaturated
D. concentrated

Explanation

To solve the question regarding the nature of the solution in the beaker containing substance 'A', we need to analyze the information provided step by step.

### Step-by-Step Solution:

1. **Understanding the Given Information**:
- We have a beaker with a solution of substance 'A'.
- When a small amount of substance 'A' is added to this solution, precipitation occurs.

2. **Defining Types of Solutions**:
- **Saturated Solution**: This is a solution where no more solute can dissolve at a given temperature. If more solute is added, it will not dissolve; instead, it will remain undissolved.
- **Supersaturated Solution**: This is a solution that contains more solute than can normally dissolve at a given temperature. When additional solute is added, it leads to precipitation of the excess solute.
- **Unsaturated Solution**: This solution can still dissolve more solute. It contains less solute than the maximum amount that can be dissolved at that temperature.
- **Concentrated Solution**: This is a solution that has a large amount of solute dissolved in it, but it may or may not be saturated.

3. **Analyzing the Situation**:
- Since precipitation occurs when a small amount of substance 'A' is added, it indicates that the solution already contains the maximum amount of solute that can be dissolved at that temperature.
- The fact that adding more solute causes precipitation suggests that the solution is not saturated, as saturated solutions would not allow any additional solute to dissolve.

4. **Conclusion**:
- Given that precipitation occurs upon adding more of substance 'A', the solution must be a **supersaturated solution**. This means it contains more solute than can normally be dissolved, and the added solute causes the excess to precipitate out.

### Final Answer:
The solution is a **supersaturated solution**.

---