Write the chemical formula of washing soda .What happens when crystals of washing soda are exposed to air ?

Explanation

### Step-by-Step Solution

1. **Identify the Chemical Formula of Washing Soda**:
- Washing soda is chemically known as sodium carbonate.
- The chemical formula is written as \( \text{Na}_2\text{CO}_3 \).
- It is also associated with water molecules. Washing soda exists as a decahydrate, meaning it contains 10 water molecules.
- Therefore, the complete formula for washing soda is \( \text{Na}_2\text{CO}_3 \cdot 10 \text{H}_2\text{O} \).

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