We can separate a pure solid from its solution by

Options

A. crystallization
B. simple distillation
C. sedimentation
D. both (a) and (b).

Explanation

To separate a pure solid from its solution, we can use the process of **crystallization**. Here’s a step-by-step explanation of how this process works:

### Step-by-Step Solution:

1. **Understanding the Solution**:
- A solution is a homogeneous mixture of two or more substances. In this case, we have a solid dissolved in a liquid.

2. **Heating the Solution**:
- To initiate crystallization, we start with a hot and saturated solution. This means that the solution has dissolved the maximum amount of solid at a given temperature.

3. **Cooling the Solution**:
- Once we have a hot and saturated solution, we allow it to cool. As the temperature decreases, the solubility of the solid in the liquid decreases.

4. **Formation of Crystals**:
- As the solution cools, the dissolved solid starts to come out of the solution and forms solid crystals. This occurs because the liquid can no longer hold all the dissolved solid.

5. **Separation of Crystals**:
- The formed crystals can then be separated from the remaining liquid (the mother liquor) by filtration. The crystals collected are pure solid substances.

6. **Conclusion**:
- Therefore, the process we use to separate a pure solid from its solution is called **crystallization**.

### Final Answer:
The correct method to separate a pure solid from its solution is **Crystallization**.

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