Most paramagnetic compound among the following
(1) CrCl3
(2) Caso4
(3) Al2(SO4)3
(4) K2 MnO4
Answers
(4) K2 MnO4...........xd
hope it helps you..
(a) K
2
Cr
2
O
7
(potassium dichromate) forms orange-red triclinic crystals and dichromate ion (Cr
2
O
7
2−
) in K
2
Cr
2
O
7
has two tetrahedral units shared through an oxygen atom. The central atom Cr is in +6 oxidation state which has electronic configuration [Ar]3d
0
4s
0
. As it does not have any unpaired electron, it is diamagnetic.
(b) NOSO
4
(vanadyl sulphate) is a hygroscopic blue solid. It features VO
2+
ion, which has vanadium in its +4 oxidation state. Since V
4+
has electronic configuration [Ar]3d
1
4s
0
, the salt is paramagnetic.
(c) (NH
4
)
2
⋅[TiCl
6
]⋅2H
2
O (ammonium chlorotitantate) is a yellow coloured crystal and Ti has +4 oxidation state. As electronic configuration of Ti
4+
is [Ar]3d
0
4s
0
, the salt is diamagnetic.
(d) K
3
[Cu(CN)
4
] (Potassium tetracyanocuprate(I)) is a white soluble complex, In it, Cu has +1 oxidation state and [Ar]3d
0
configuration. Hence, it is paramagnetic.