JEE Main 2005ChemistryD And F Block ElementsInner Transition Elements Lanthanoids And ActinoidseasyMCQ

JEE Main 2005 — D And F Block Elements Question with Solution

From: AIEEE 2005

Question

The lanthanide contraction is responsible for the fact that :

Choose an option

Show full solutionCorrect option: C
Correct answer
CZr and Hf have about the same radius

Step-by-step explanation

AIEEE 2005 Chemistry - d and f Block Elements Question 210 English Explanation
In the entire d-block,

Only in group 3, the size increase from top to bottom due to increase of no of shells in an atom. That is why size of Sc < Y < La. And shell size in group 3 is 3d < 4d < 5d.

But from group 4 to 12, the size of 3d < 4d but 4d 5d due to lanthanide contraction. That is why Zr and Hf have about the same radius.

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About this question

This is a previous-year question from JEE Main 2005, 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.