An amalgam is an alloy of mercury with another metal. While many metals can form amalgams, iron does not readily form one because it has a very low affinity for mercury under normal . On the other hand, metals like zinc, copper, and magnesium can form amalgams. Science and Technology 607 340. Assertion (A): Sodium metal is stored under kerosene. Reason (R): Metallic sodium melts when exposed to air.
✓ Correct answer: c) A is true but R is false
ExplanationAssertion (A) is true: Sodium is highly reactive and reacts vigorously with air (oxygen) and moisture, which could lead to fire or explosion.Storing it under kerosene prevents contact with air and moisture, ensuring safety.Reason (R) is false: Sodium does not melt when exposed to air but instead reacts with oxygen and moisture to form sodium oxide (Na₂O) or sodium hydroxide (NaOH).The melting of sodium occurs only when it is heated to its melting point (98°C), which is unrelated to its reaction with air.Directions: The following two Items consist of statements.One labeled as the ‘Assertion (A)’ and the other as ‘Reason (R)’.You have to answer these items using the code given below: (1998) 341
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