Amongst the following the number of oxide(s) which are paramagnetic in nature is $\mathrm{Na}_{2} \mathrm{O}, \mathrm{KO}_{2}, \mathrm{NO}_{2}, \mathrm{~N}_{2} \mathrm{O}, \mathrm{ClO}_{2}, \mathrm{NO}, \mathrm{SO}_{2}, \mathrm{Cl}_{2} \mathrm{O}$

JEE Main · 2022 · 27 Jul 2022 · Shift 1 · Chemical Bonding and Molecular Structure

Amongst the following the number of oxide(s) which are paramagnetic in nature is

Na_{2} O, KO_{2}, NO_{2}, N_{2} O, ClO_{2}, NO, SO_{2}, Cl_{2} O

Answer: 4

A species is paramagnetic if it has unpaired electrons.

Analyzing each oxide:

$Na X_{2} O$ : All electrons paired → diamagnetic
$KO X_{2}$ : Superoxide ion $O X_{2} X^{-}$ has one unpaired electron → paramagnetic
$NO X_{2}$ : Has one unpaired electron (odd number of electrons, 17 total) → paramagnetic
$N X_{2} O$ : All electrons paired → diamagnetic
$ClO X_{2}$ : Has one unpaired electron (odd number of electrons, 19 total) → paramagnetic
$NO$ : Has one unpaired electron (odd number of electrons, 15 total) → paramagnetic
$SO X_{2}$ : All electrons paired → diamagnetic
$Cl X_{2} O$ : All electrons paired → diamagnetic

Paramagnetic oxides:

KO X_{2}

NO X_{2}

ClO X_{2}

NO

Therefore, the answer is 4.

JEE Main · 2022 · 27 Jul 2022 · Shift 1 · Integer answer