JEE Main · 2022 · 26 Jun 2022 · Shift 2 · Coordination Compounds

Reaction of

[Co (H_{2} O)_{6}]^{2 +}

with excess ammonia and in the presence of oxygen results into a diamagnetic product. Number of electrons present in

t_{2 g}

-orbitals of the product is

____

Answer: 6

Solution

The reaction is:

[Co (H_{2} O)_{6}]^{2 +} + NH_{3} (excess) + O_{2} \to [Co (NH_{3})_{6}]^{3 +}

.

Since the product is diamagnetic, it must be a low-spin complex.

Co^{3 +}

has electronic configuration

3 d^{6}

.

In a low-spin octahedral complex with strong-field ligand

NH_{3}

, the configuration is

t_{2 g}^{6} e_{g}^{0}

.

Therefore, the number of electrons in

t_{2 g}

orbitals is 6.

JEE Main · 2022 · 26 Jun 2022 · Shift 2 · Integer answer

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