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प्रश्न
Assertion (A): Transition metals have high enthalpy of atomisation.
Reason (R): Greater number of unpaired electrons in transition metals results in weak metallic bonding.
विकल्प
Both (A) and (R) are true and (R) is the correct explanation of (A).
Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(A) is true, but (R) is false.
(A) is false, but (R) is true.
उत्तर
(A) is true, but (R) is false.
Explanation:
The assertion (A) is true: Transition metals exhibit a high enthalpy of atomization. This is owing to the strong metallic bonds found in these metals.
The reasoning (R) is false: The existence of unpaired electrons in transition metals causes stronger, rather than weaker, metallic bonding. The delocalization of d and s electrons across the metal lattice helps to form strong metallic connections.
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