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. unsturated
D. concentrated

Explanation

To solve the question, we need to analyze the behavior of the solution of substance 'A' when more of substance 'A' is added. The key point is that precipitation occurs when a small amount of 'A' is added to the solution. Let's go through the options step by step.

### Step 1: Understand the Definitions
1. **Saturated Solution**: A solution that has reached its maximum capacity to dissolve a solute. No more solute can dissolve in it, and if additional solute is added, it does not dissolve but remains undissolved.

2. **Supersaturated Solution**: A solution that contains more solute than it can theoretically hold at a given temperature. When more solute is added, it causes precipitation because the solution is unstable.

3. **Unsaturated Solution**: A solution that can still dissolve more solute. If more solute is added, it will dissolve without any precipitation.

4. **Concentrated Solution**: A solution that has a high amount of solute relative to the solvent. It does not necessarily mean that it is saturated; it can still dissolve more solute.

### Step 2: Analyze the Given Situation
In the problem, we are told that when a small amount of substance 'A' is added to the solution, precipitation occurs. This indicates that the solution cannot accommodate any more of substance 'A' without causing some of it to come out of the solution as a solid.

### Step 3: Eliminate Options
- **Saturated Solution**: If the solution were saturated, adding more solute would not cause precipitation; it would simply not dissolve. Thus, this option is incorrect.

- **Unsaturated Solution**: If the solution were unsaturated, adding more solute would result in it dissolving completely, not precipitating. Thus, this option is also incorrect.

- **Concentrated Solution**: While a concentrated solution may contain a lot of solute, it does not imply that it is saturated. Therefore, this option is also incorrect.

### Step 4: Identify the Correct Option
The only option left is **Supersaturated Solution**. In a supersaturated solution, adding more solute causes precipitation because the solution is holding more solute than it can normally accommodate at that temperature.

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

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