A gas formed in a soda-acid fire extinguisher and puts out fires is _____.

Options

A. Nitric acid
B. Carbon dioxide
C. Sulphuric acid
D. Nitrogen dioxide

Answer

To answer the question, "A gas formed in a soda-acid fire extinguisher and puts out fires is _____," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of a Soda-Acid Fire Extinguisher**:
- A soda-acid fire extinguisher typically contains baking soda (sodium bicarbonate, NaHCO3) and sulfuric acid (H2SO4).

2. **Understand the Reaction**:
- When baking soda reacts with sulfuric acid, a chemical reaction occurs. The balanced equation for this reaction is:
\[ 2 \text{NaHCO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{Na}_2\text{SO}_4 + 2 \text{H}_2\text{O} + 2 \text{CO}_2 \]
- From this equation, we can see that carbon dioxide (CO2) is one of the products formed in the reaction.

3. **Role of Carbon Dioxide in Fire Extinguishing**:
- Carbon dioxide is effective in extinguishing fires because it displaces oxygen in the air. Fire requires oxygen to sustain combustion, so by cutting off the oxygen supply, CO2 helps to extinguish the fire.

4. **Conclusion**:
- Therefore, the gas formed in a soda-acid fire extinguisher that puts out fires is carbon dioxide (CO2).

### Final Answer:
The gas formed in a soda-acid fire extinguisher and puts out fires is **carbon dioxide (CO2)**.

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