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Chemistry Question 61 – NEET-UG 2026

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Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Generally, 3d transition metals have high melting points. Reason R : Involvement of 3d-electrons in addition to 4s-electrons in the interatomic metallic bonding. In light of the above statements, choose the most appropriate answer from the options given below:

Recall the general physical properties of transition metals, specifically their melting points.

Step 1: Evaluate Assertion A✦ Active

Assertion A states that 3d transition metals generally have high melting points. This statement is correct. Transition metals are known for their high melting and boiling points due to strong metallic bonding.

Step 2: Evaluate Reason R○ Expand

Reason R states that the involvement of 3d-electrons in addition to 4s-electrons contributes to interatomic metallic bonding. This statement is also correct. The presence of partially filled d-orbitals allows for strong metallic bonding due to the participation of a large number of valence electrons (both 4s and 3d) in delocalized metallic bonds.

Step 3: Determine if Reason R explains Assertion A○ Expand

The strong metallic bonding, resulting from the involvement of both 4s and 3d electrons, requires a significant amount of energy to overcome, leading to high melting points. Therefore, Reason R provides a correct explanation for Assertion A.

💡 Teacher's Secret Hint

Remember that the strength of metallic bonding directly correlates with melting point.

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