JEE Main 2021 — Chemical Bonding And Molecular Structure Question with Solution
From: JEE Main 2021 (Online) 1st September Evening Shift
Question
Number of paramagnetic oxides among the following given oxides is ____________.
Li2O, CaO, Na2O2, KO2, MgO and K2O
Li2O, CaO, Na2O2, KO2, MgO and K2O
Choose an option
Show full solutionCorrect option: A
Correct answer
A1
Step-by-step explanation
Li2O 2Li+ O2
CaO Ca2+ O2
Na2O2 2Na+ O
KO2 O
MgO Mg2+ O2
K2O 2K+ O2
O2 Complete octet, diamagnetic
has 18 electrons.
Moleculer orbital configuration of is
Here is no unpaired electron so it is diamagnetic.
has 17 electrons.
Moleculer orbital configuration of is
Here is 1 unpaired electron so it is paramagnetic.
CaO Ca2+ O2
Na2O2 2Na+ O
KO2 O
MgO Mg2+ O2
K2O 2K+ O2
O2 Complete octet, diamagnetic
has 18 electrons.
Moleculer orbital configuration of is
Here is no unpaired electron so it is diamagnetic.
has 17 electrons.
Moleculer orbital configuration of is
Here is 1 unpaired electron so it is paramagnetic.
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This is a previous-year question from JEE Main 2021, covering the Chemical Bonding And Molecular Structure 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.