NEET Practice Questions (MCQs) with Answers & Solutions

Given complex compound is M(en)₂(C₂O₄)]Cl Let oxidation number of M is x

x-2-1 = 0

or x = + 3

Now, as coordination number is defined as the total number of binding sites attached to the metal. Hence, in the given complex coordination number is 6.

Hence, the sum of coordination number and oxidation number of the metal M is $6+3=9$.

Key Concept When complex ion as an anion, the name of the  metal ends with suffix-ate along with its oxidation number in the complex ion. [Fe(CN)₆]^3-=Hexacyanidoferate (III) ion.

The CFSE for octahedral complex is given by:-
CFSE=[-0.4 t_2g e^- + 0.6e_ge^-]
For Mn³⁺,[3d⁴] → t³ 2_ge¹g

∴  CFSE≈[-0.4X3+0.6x1]=-0.6

For Fe³⁺,[3d⁵] →t³_2g eg²

CFSE=[-(0.4x3)+(0.6x2)]=0
For Co²⁺,[3d⁷] →t⁵_2g e²g

CFSE=[(-0.4x5)+(2x0.6)]=-0.8
For Co³⁺,[3d⁶] →t⁴_2g eg²

CFSE=[(-0.4x4)+(2x0.6)]=-0.4

(b) cis-platin is known as anticancer agent. The formula for cis-platin is cis-[PtCl₂(NH₃)₂].Here, the word cis refers to cis geometrical isomer of [PtCl₂(NH₃)₂].

The d-electron configuration of Co2+ is d7. This configuration has no unpaired electrons, making [Co(H2O)6]2+ diamagnetic. The other options have unpaired electrons, exhibiting paramagnetic behavior.