MCQ Questions for Class 12 Engineering Chemistry Coordination Compounds Quiz 15

Which of the following complex compounds will exhibit highest paramagnetic behaviour? (At. No.

$Ti = 22, Cr = 24, Co = 27, Zn = 30$ )

Explanation

$[Zn(NH_3)_6]^{2+}$ : In this complex because of

$3d^{10}$ configuration no

$(n - 1)d$ orbital is available for

$d^2 sp^3$ hybridisation and thus forms outer orbital complex. The complex is diamagnetic.

b.

$[Ti(NH_3)_6]^{3+}$ :

$Ti$ has

$3d^1$ configuration and thus has one unpaired electron.

c.

$[Cr(NH_3)_6]^{3+}$ : The complex is inner orbital complex but

$3d^3$ configuration has three unpaired electrons with weak as well as with strong field ligand.

d.

$[Co(NH_3)_6]^{3+}$ : The cobalt ion is in

$+3$ oxidation state with

$3d^6$ configuration and thus is a diamagnetic octahedral complex.

If d-d transition energy and electron pair energy for an octahedral complex have values

$45000$

$cm^{-1}$ and

$14000$

$cm^{-1}$ the value of CFSE is:

CBSE Questions for Class 12 Engineering Chemistry Coordination Compounds Quiz 15 - MCQExams.com