Q.Sodium is stored in

Sodium metal is stored under kerosene (a hydrocarbon liquid) to protect it from reacting with moisture and oxygen in air.

Sodium is a soft, highly reactive alkali metal. It reacts vigorously and exothermically with water:

2Na + 2H2O -> 2NaOH + H2 (the reaction can even ignite the liberated hydrogen)

It also readily reacts with atmospheric oxygen and moisture if left exposed, tarnishing and eventually catching fire. To prevent contact with air and water, freshly cut sodium is stored fully immersed in kerosene (a non-polar hydrocarbon liquid) in which sodium does not dissolve or react, so it stays protected while remaining easy to retrieve for use.

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Sodium metal is stored under kerosene because kerosene is chemically inert to sodium and excludes atmospheric oxygen and moisture, both of which react with sodium.

Sodium is a soft, highly reactive alkali metal. It reacts readily with:

• Oxygen in air, forming a layer of sodium oxide/peroxide (tarnishing and eventually corroding the metal).
• Moisture (water vapour), reacting vigorously (even violently) to form sodium hydroxide and hydrogen gas: 2Na + 2H2O -> 2NaOH + H2. …