Which of the following salt becomes plaster of paris on being appropriately hydrated

Options

A. `ZnCO_(3)`
B. `CaSO_(4)`
C. `MgSO_(4)`
D. `CaCO_(3)`

Explanation

To determine which salt becomes plaster of Paris upon appropriate hydration, we need to analyze the options provided.

### Step-by-Step Solution:

1. **Understanding Plaster of Paris**:
Plaster of Paris is chemically known as calcium sulfate hemihydrate, represented as CaSO4·1/2H2O or CaSO4·0.5H2O. It is formed when calcium sulfate (CaSO4) is partially hydrated.

2. **Identifying the Hydration**:
The term "appropriately hydrated" refers to the specific addition of water to a certain form of calcium sulfate.

3. **Recognizing the Chemical Formula**:
The correct formula for plaster of Paris is CaSO4·1/2H2O. This indicates that for every one molecule of calcium sulfate, there is half a molecule of water, which corresponds to the hemihydrate form.

4. **Conclusion**:
Based on the above understanding, the salt that becomes plaster of Paris when appropriately hydrated is **CaSO4·1/2H2O**.

### Final Answer:
The salt that becomes plaster of Paris upon appropriate hydration is **CaSO4·1/2H2O** (calcium sulfate hemihydrate).