JEE Main 2023ChemistryClassification of Elements and Periodicity in PropertiesEasyMCQ

JEE Main 2023 — Classification of Elements and Periodicity in Properties Question with Solution

JEE Main 2023 (29 Jan Shift 2)

Question

Given below are two statements:

Statement I: The decrease in first ionization enthalpy from B to Al is much larger than that from Al to Ga.

Statement II: The d orbitals in Ga are completely filled.

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

Choose an option

Show full solutionCorrect option: B
Correct answer
BBoth the statements I and II are correct

Step-by-step explanation

First ionization enthalpy (IE1) of B, Al, Ga are 801, 577 and 579 kJ/mol respectively. 

As decrease in first ionization enthalpy is much larger from B to Al. ∆IE1 of B and Al is greater than ∆IE1 of Al and Ga. So, the statement I is correct.

This is due to completely filled d-orbitals in Ga and d-electron have low screening effect to compensate the increase in nuclear charge. So, The statement II is also correct.

Hence, the correct option is B.

 

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About this question

This is a previous-year question from JEE Main 2023, covering the Classification of Elements and Periodicity in Properties 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.