The reason behind storing the potassium and sodium in kerosene is because they are highly reactive in air and could burn any time. They are preserved in kerosene or dry mineral oil. These metals are stored in kerosene to protect this element from moisture or water content.

Introduction:
Sodium and potassium are highly reactive metals that can easily react with water and air. To prevent them from reacting, they are stored in kerosene oil.

Reasons for storing sodium and potassium in kerosene oil:

1. Prevent oxidation: Sodium and potassium are highly reactive metals that can easily react with air and water to form oxides and hydroxides. These compounds can easily catch fire when exposed to air. Therefore, to prevent oxidation, sodium and potassium are stored in kerosene oil.

2. Prevent water reaction: Sodium and potassium are highly reactive with water, and they can easily react with water to produce hydrogen gas and heat. This reaction can be very violent, and it can lead to an explosion. Therefore, to prevent this reaction, sodium and potassium are stored in kerosene oil.

3. Kerosene oil is non-polar: Kerosene oil is a non-polar solvent, which means that it does not contain any electric charge. Therefore, it does not react with the metals, and it does not dissolve the metal ions. This property of kerosene oil makes it an ideal solvent for storing sodium and potassium.

4. Prevent fire: Sodium and potassium are highly flammable metals that can easily catch fire. Kerosene oil is a non-flammable solvent, and it does not support combustion. Therefore, storing sodium and potassium in kerosene oil prevents any fire hazard.

Conclusion:
In conclusion, sodium and potassium are highly reactive metals that can easily react with air and water. To prevent them from reacting, they are stored in kerosene oil. Kerosene oil prevents oxidation, water reaction, fire, and it is a non-polar solvent.