AIIMS2004ChemistryCoordination Compounds
Assertion : The [ Ni ( en )₃ ] Cl ₂ (en = ethylene diamine) has lower stability than [ Ni ( NH ₃ )₆ ] Cl ₂ . Reason : In [ Ni ( en )₃ ] Cl ₂ the geometry of Ni is trigonal bipyramidal.
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion
- BIf both assertion and reason are true but reason is not the correct explanation of assertion
- CIf assertion is true but reason is false
- DIf both assertion and reason are false.
Correct answer
D. If both assertion and reason are false.
Step-by-step solution
[ Ni ( en )₃ ] Cl ₂ is a chelating compound and chelated complexes are more stable than similar complexes with unidentate ligands as dissociation of the complex involves breaking of two bonds rather than one. In [ Ni ( en )₃ ] Cl ₂, Ni with d^8 configuration shows octahedral geometry. Six electrons will occupy the t_ 2 g orbitals and two electrons will occupy the e_g orbitals.