Which two chemicals react in a soda-acid fire extinguisher?

Options

A. Sodium bicarbonate and hydrochloric acid
B. Sodium hydroxide and hydrochloric acid
C. Sodium bicarbonate and sulphuric acid
D. Hydrochloric acid and sulphuric acid

Answer

### Step-by-Step Solution:

1. **Identify the Components of a Soda-Acid Fire Extinguisher**:
- The name "soda-acid fire extinguisher" indicates that it contains soda (which usually refers to sodium bicarbonate) and an acid.

2. **Determine the Chemicals Involved**:
- The two primary chemicals that react in a soda-acid fire extinguisher are:
- **Sodium Bicarbonate (NaHCO3)**, commonly known as baking soda.
- **Sulfuric Acid (H2SO4)**.

3. **Write the Chemical Reaction**:
- When sodium bicarbonate reacts with sulfuric acid, the following reaction occurs:
\[ \text{NaHCO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{Na}_2\text{SO}_4 + \text{H}_2\text{O} + \text{CO}_2 \]
- This reaction produces sodium sulfate, water, and carbon dioxide.

4. **Understand the Role of the Products**:
- The carbon dioxide produced helps to smother the fire by displacing oxygen, while the water can help cool the flames.

5. **Conclusion**:
- Therefore, the two chemicals that react in a soda-acid fire extinguisher are **Sodium Bicarbonate (NaHCO3)** and **Sulfuric Acid (H2SO4)**.