What is Epsom salt ? What is the action of heat on it ?

Explanation

### Step-by-Step Solution:

1. **Definition of Epsom Salt**:
Epsom salt is a chemical compound known as magnesium sulfate heptahydrate. Its chemical formula is \( \text{MgSO}_4 \cdot 7\text{H}_2\text{O} \). It is commonly used in various applications, including agriculture, gardening, and as a bath salt.

2. **Composition of Epsom Salt**:
Epsom salt consists of magnesium sulfate (MgSO4) combined with seven molecules of water (7H2O). This water is known as water of crystallization, which is integral to the structure of the compound.

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