MolSynapsequestion bank

MolSynapse / Question bank / d- and f-Block Elements / Colour and magnetic properties

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3df159

Which of the following complex ions have a spin-only magnetic moment of zero?

A $[Ni (CN) X_{4}] X^{2 -}$
B $[Co (NH X_{3}) X_{6}] X^{3 +}$
C $[Fe (CN) X_{6}] X^{4 -}$
D $[CoF X_{6}] X^{3 -}$

Answer: A, B, C

[Fe (CN) X_{6}] X^{4 -}

is low-spin Fe(II)

t_{2 g}^{6}

,

[Co (NH X_{3}) X_{6}] X^{3 +}

is low-spin Co(III)

t_{2 g}^{6}

, and

[Ni (CN) X_{4}] X^{2 -}

is square-planar Ni(II)

d^{8}

; all are diamagnetic.

[CoF X_{6}] X^{3 -}

is high-spin Co(III) with 4 unpaired electrons.

Practice d- and f-Block Elements More on Colour and magnetic properties

Previous questionNext question

More questions on Colour and magnetic properties