The number of atoms in one molecule of Epsom salt is

Explanation

To determine the total number of atoms in one molecule of Epsom salt (Magnesium Sulfate Heptahydrate), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Chemical Formula**:
Epsom salt is represented by the formula \( \text{MgSO}_4 \cdot 7 \text{H}_2\text{O} \).

2. **Break Down the Components**:
- The formula consists of two parts: \( \text{MgSO}_4 \) and \( 7 \text{H}_2\text{O} \).
- \( \text{MgSO}_4 \) contains:
- 1 Magnesium (Mg) atom
- 1 Sulfur (S) atom
- 4 Oxygen (O) atoms
- \( 7 \text{H}_2\text{O} \) contains:
- 7 Water molecules, each containing:
- 2 Hydrogen (H) atoms
- 1 Oxygen (O) atom
- Therefore, for 7 water molecules:
- Total Hydrogen atoms = \( 7 \times 2 = 14 \)
- Total Oxygen atoms = \( 7 \times 1 = 7 \)

3. **Calculate Total Atoms**:
- From \( \text{MgSO}_4 \):
- Total atoms = 1 (Mg) + 1 (S) + 4 (O) = 6 atoms
- From \( 7 \text{H}_2\text{O} \):
- Total atoms = 14 (H) + 7 (O) = 21 atoms
- Combine both parts:
- Total atoms in Epsom salt = 6 (from \( \text{MgSO}_4 \)) + 21 (from \( 7 \text{H}_2\text{O} \)) = 27 atoms

### Final Answer:
The total number of atoms in one molecule of Epsom salt is **27**.

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