Back to Directory
NEET CHEMISTRYMedium

Given below are two statements: Statement I: Both [Co(NH3)6]3+[Co(NH_3)_6]^{3+} and [CoF6]3[CoF_6]^{3-} complexes are octahedral but differ in their magnetic behaviour. Statement II: [Co(NH3)6]3+[Co(NH_3)_6]^{3+} is diamagnetic whereas [CoF6]3[CoF_6]^{3-} is paramagnetic. In the light of the above statements, choose the correct answer from the options given below:

A

Both Statement I and Statement II are False.

B

Statement I is True and Statement II is False.

C

Statement I is False but Statement II is True.

D

Both Statement I and Statement II are True.

Step-by-Step Solution

Both [Co(NH3)6]3+[Co(NH_3)_6]^{3+} and [CoF6]3[CoF_6]^{3-} have the central metal ion CoCo in the +3 oxidation state, which has a 3d63d^6 electronic configuration. In [Co(NH3)6]3+[Co(NH_3)_6]^{3+}, NH3NH_3 acts as a strong field ligand, causing the pairing of 3d3d electrons against Hund's rule. This results in a t2g6eg0t_{2g}^6 e_g^0 configuration with no unpaired electrons. It undergoes d2sp3d^2sp^3 hybridization, forming an inner-orbital octahedral complex that is diamagnetic. In [CoF6]3[CoF_6]^{3-}, FF^- is a weak field ligand and does not cause the pairing of 3d3d electrons. It has a t2g4eg2t_{2g}^4 e_g^2 configuration with four unpaired electrons. It undergoes sp3d2sp^3d^2 hybridization, forming an outer-orbital octahedral complex that is highly paramagnetic. Therefore, both complexes are octahedral but have different magnetic behaviours, making both Statement I and Statement II true.

Practice Mode Available

Master this Topic on Sushrut

Join thousands of students and practice with AI-generated mock tests.

Get Started