JEE Main 2023 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 15 April 2023, Shift 1, Chemistry Q87

Question 87 of 90 in this shift, Chemistry question 27 of 30, Section B.

The total number of isoelectronic species from the given set is __________.

\mathrm{O^{2-}, F^-, Al, Mg^{2+}, Na^+, O^+, Mg, Al^{3+}, F}

Official answer

NTA final key.

Chapter: Classification of Elements and Periodicity in Properties
Topic: Periodic Trends
Idea tested: Isoelectronic Species Radii Comparison

Same idea in other shifts

Asked 10× in all

5 Apr 2024, Shift 1 · Q66The statement(s) that are correct about the species $\mathrm{O^{2-}}$ , $\mathrm{F^-}$ , $\mathrm{Na^+}$ and $\mathrm{Mg^{2+}}$ . (A) All are…EasyOther
1 Feb 2024, Shift 1 · Q65In case of isoelectronic species the size of $\mathrm{F^-}$ , Ne and $\mathrm{Na^+}$ is affected by :EasySingle correct
27 Jun 2022, Shift 1 · Q65Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The ionic radii…EasyAssertion–reason
27 Jun 2022, Shift 2 · Q65The correct order of increasing ionic radii isEasySingle correct
27 Aug 2021, Shift 2 · Q32The correct order of ionic radii for the ions, $\mathrm{P^{3-}}$ , $\mathrm{S^{2-}}$ , $\mathrm{Ca^{2+}}$ , $\mathrm{K^{+}}$ ,…EasySingle correct
25 Jul 2021, Shift 1 · Q33The ionic radii of $\mathrm{K^+}$ , $\mathrm{Na^+}$ , $\mathrm{Al^{3+}}$ and $\mathrm{Mg^{2+}}$ are in the order :EasySingle correct
25 Jul 2021, Shift 2 · Q34The ionic radii of $\mathrm{F^{-}}$ and $\mathrm{O^{2-}}$ respectively are 1.33 Å and 1.4 Å, while the covalent radius of N is 0.74 Å. The…EasySingle correct
18 Mar 2021, Shift 1 · Q34The ionic radius of $\mathrm{Na^+}$ ion is 1.02 Å. The ionic radii (in Å) of $\mathrm{Mg^{2+}}$ and $\mathrm{Al^{3+}}$ , respectively, are :EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.