What are freons ?

Explanation

### Step-by-Step Solution:

1. **Definition of Freons**: Freons are a type of chemical compound known as chlorofluorocarbons (CFCs).

2. **Composition of Freons**: These compounds consist of three elements: carbon (C), chlorine (Cl), and fluorine (F).

3. **Origin of Freons**: Freons are produced as volatile derivatives of hydrocarbons, specifically methane (CH₄), ethane (C₂H₆), and propane (C₃H₈).

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