JEE Main 2005 — D And F Block Elements Question with Solution
From: AIEEE 2005
Question
Which of the following factors may be regarded as the main cause of lanthanide
contraction?
Choose an option
Show full solutionCorrect option: C
Correct answer
CPoorer shielding of 5d electrons by 4f electrons
Step-by-step explanation
The main reason of lanthanide contraction is, poor shielding of 4f electrons on the outer most shell electrons.
In lanthanides, there is poorer shielding of electrons by electrons resulting in greater attraction of the nucleus over electrons and reduction of the atomic radii.
In lanthanides, there is poorer shielding of electrons by electrons resulting in greater attraction of the nucleus over electrons and reduction of the atomic radii.
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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.