Question

Molecules / ions and their magnetic properties are given below.

	Molecule/Ion		Magnetic property
i	$C _{6} H _{6}$	1	Antiferromagnetic
ii	$CrO _{2}$	2	Ferrimagnetic
iii	$MnO$	3	Ferromagnetic
iv	$Fe _{3} O _{4}$	4	Paramagnetic
v	$Fe ^{3+}$	5	Diamagnetic

The correctly matched pairs in the above is

• A. $i-5 \,ii-3\, iii-2 \,iv-1\,v-4$
• B. $i-3 ii-5 iii-1 iv-4 v-2$
• C. $i-5 ii-3 iii-1 iv-2 v-4$
• D. $i-5 ii-3 iii-1 iv-4 v-2$
• E. $i-4 ii-5 iii-1 iv-2 v-3$

Answer 1

Answer: (C)

$C _{6} H _{6}$ is a diamagnetic substance, as it is weakly repelled by a magnetic field.

$CrO _{2}$ is a ferromagnetic substance, which is attracted very strongly by a magnetic field.

$MnO$ is an antiferromagnetic substance as its domains cancel out each other's magnetic moment.

$Fe _{3} O _{4}$ (magnetite) is a ferrimagnetic substance because in it the magnetic moments of the domains are aligned in parallel and anti-parallel direction in unequal number.

$Fe ^{3+}\left(3 d^{5}\right)$ is paramagnetic because of the presence of unpaired electrons.

Thus, the correct match is

$i -5, ii -3, iii -1, iv -2, v -4$