Epsom salt is

Options

A. `MgSO_(4) " "7H_(2)O`
B. `Mg(OH)_(2)`
C. `2CaSO_(4)" "H_(2)O`
D. `BaSO_(4)`

Answer

To determine what Epsom salt is, we need to analyze the options provided in the question.

### Step-by-step Solution:

1. **Understanding Epsom Salt**:
Epsom salt is commonly known as magnesium sulfate heptahydrate. This means it contains magnesium, sulfur, and oxygen, along with water molecules.

2. **Analyzing the Options**:
- **Option A: MgSO4 x 7H2O**: This represents magnesium sulfate with seven water molecules, which is indeed the definition of Epsom salt.
- **Option B: Mg(OH)2**: This is magnesium hydroxide, which is not Epsom salt.
- **Option C: CaSO4 x H2O**: This is calcium sulfate with one water molecule, commonly known as gypsum, which is also not Epsom salt.
- **Option D: BaSO4**: This is barium sulfate, which is another sulfate salt but not related to Epsom salt.

3. **Conclusion**:
Based on the analysis of the options, the correct answer is **Option A: MgSO4 x 7H2O**. This confirms that Epsom salt is magnesium sulfate heptahydrate.

### Final Answer:
Epsom salt is **MgSO4 x 7H2O**.

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