JEE Main 2023ChemistryD And F Block ElementsInner Transition Elements Lanthanoids And ActinoidseasyMCQ

JEE Main 2023D And F Block Elements Question with Solution

From: JEE Main 2023 (Online) 12th April Morning Shift

Question

Given below are two statement: one is labelled as Assertion and the other is labelled as Reason

Assertion A: electrons can participate in bonding to a far greater extent than electrons

Reason R: orbitals are not as buried as orbitals

In the light of the above statements, choose the correct answer from the options given below

Choose an option

Show full solutionCorrect option: A
Correct answer
ABoth A and R are true and R is the correct explanation of A

Step-by-step explanation

Assertion A: 5f electrons can participate in bonding to a far greater extent than 4f electrons

This is correct. In actinides (elements in which 5f orbitals are being filled), the 5f electrons can participate in bonding. This contrasts with lanthanides (elements in which 4f orbitals are being filled), where the 4f electrons largely do not participate in bonding.

Reason R: 5f orbitals are not as buried as 4f orbitals

This is also correct. The term "buried" refers to the degree to which an orbital is shielded from the outside environment by other electrons. The 5f orbitals are less shielded, or less "buried," than the 4f orbitals. This means they are more exposed to the outside environment and can more readily interact with other atoms to form bonds. This is the reason why 5f electrons can participate in bonding to a greater extent than 4f electrons.

Therefore, both A and R are true, and R is the correct explanation of A.

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About this question

This is a previous-year question from JEE Main 2023, covering the D And F Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.