Sodium reacts vigorouly with oxygen at room temperature to from sodium oxide. To prevent explosion they are stored in ______.

Options

A. oil
B. water
C. kerosene
D. sand

Answer

**Step-by-Step Solution:**

1. **Understanding the Reaction**: Sodium (Na) is a highly reactive metal that reacts vigorously with oxygen (O2) at room temperature. This reaction produces sodium oxide (Na2O).

2. **Identifying the Product**: The chemical equation for the reaction can be written as:
\[ 4Na + O_2 \rightarrow 2Na_2O \]
This shows that sodium reacts with oxygen to form sodium oxide.

3. **Recognizing the Hazard**: The reaction between sodium and oxygen is highly exothermic, meaning it releases a lot of heat, which can lead to an explosion if not controlled.

4. **Preventing the Reaction**: To prevent sodium from reacting with oxygen and causing an explosion, it is essential to store it in a medium that does not allow contact with air (oxygen).

5. **Choosing the Storage Medium**: Sodium is stored in kerosene. Kerosene is a type of oil that does not react with sodium and effectively prevents it from coming into contact with oxygen in the air.

6. **Conclusion**: Therefore, the correct answer to the question is that sodium is stored in **kerosene** to prevent explosive reactions.

**Final Answer**: Sodium is stored in **kerosene**.

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