Assertion (A): Sodium metal is stored under kerosene. Reason (R): Metallic sodium melts when exposed to air.
- ABoth A and R are true, and R is the correct explanation of A
- BBoth A and R are true, but R is NOT a correct explanation of A
- CA is true, but R is falseCorrect
- DA is false, but R is true
Explanation
Assertion A is true because sodium is an extremely reactive alkali metal. It reacts vigorously with the oxygen and moisture present in the air. To prevent this accidental reaction and protect it from oxidation, it is stored submerged in kerosene.
Reason R is false because sodium does not melt when exposed to air. Instead, it reacts chemically with oxygen to form sodium oxide and with moisture to form sodium hydroxide. This is a chemical reaction rather than a physical change of state like melting. Since the assertion is correct but the reason is incorrect, option C is the right answer.
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