What is fire foam?

Answer

**Step-by-Step Text Solution:**

1. **Definition of Fire Foam**: Fire foam is a type of foam specifically designed for fire suppression. It is used to extinguish fires, particularly those involving flammable liquids.

2. **Composition of Fire Foam**: Fire foam is created by mixing a solution of sodium bicarbonate (NaHCO₃) and alum (potassium aluminum sulfate). This mixture generates carbon dioxide gas, which is crucial for its fire-suppressing properties.

3. **Mechanism of Action**: The primary function of fire foam is to coat the fuel source. By doing so, it cools the fire and prevents the fuel from coming into contact with oxygen.

4. **Prevention of Combustion**: By creating a barrier between the fuel and oxygen, fire foam effectively suppresses combustion, thereby extinguishing the fire.

5. **Usage**: Fire foam is commonly used in fire extinguishers and firefighting equipment, particularly in situations where flammable liquids are involved.

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