Which of these fire extinguishing methods can be used to put out an oil fire?

Options

A. Pour water on the fire
B. Use a soda-acid fire extinguisher
C. Use a carbon dioxide fire extinguisher
D. All of these

Answer

To determine which fire extinguishing method can be used to put out an oil fire, we will analyze the given options step by step.

### Step 1: Evaluate the first option - Pour water on the fire
- **Analysis**: Water is denser than oil. When water is poured on an oil fire, it sinks to the bottom, and the oil continues to burn on top. This means that the fire will not be extinguished, and in fact, it can spread.
- **Conclusion**: This method is ineffective for extinguishing an oil fire.

### Step 2: Evaluate the second option - Use a soda acid fire extinguisher
- **Analysis**: A soda acid fire extinguisher contains sodium bicarbonate (NaHCO3) and reacts with sulfuric acid (H2SO4) to produce sodium sulfate (Na2SO4), water (H2O), and carbon dioxide (CO2). While carbon dioxide can help smother the fire by cutting off the oxygen supply, the water produced can actually promote the fire, as it does not effectively extinguish an oil fire.
- **Conclusion**: This method is also ineffective for extinguishing an oil fire.

### Step 3: Evaluate the third option - Use a carbon dioxide fire extinguisher
- **Analysis**: A carbon dioxide fire extinguisher releases CO2, which acts as a blanket around the fire, cutting off the oxygen supply. This is effective for extinguishing oil fires because it does not introduce any water, which could promote the fire.
- **Conclusion**: This method is effective for extinguishing an oil fire.

### Step 4: Evaluate the fourth option - All of these are wrong
- **Analysis**: Since we have established that the third option (using a carbon dioxide fire extinguisher) is effective, this statement is incorrect.
- **Conclusion**: This option is not valid.

### Final Answer
The correct method to put out an oil fire is to **use a carbon dioxide fire extinguisher**.

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