NEETChemistryStructure of Atom
Which of the following pairs of transition metal ions has the same spin-only magnetic moment?
Options
- ACr ²⁺ and Fe ³⁺
- BV ³⁺ and Ni ²⁺
- CMn ²⁺ and Co ²⁺
- DTi ²⁺ and V ²⁺
Correct answer
B. V ³⁺ and Ni ²⁺
Step-by-step solution
The spin-only magnetic moment depends on the number of unpaired electrons ( n ) according to the formula = n(n+2) B.M. Ions with the same number of unpaired electrons will exhibit the same spin-only magnetic moment. Let us write the electronic configurations to determine n for each ion: Cr ²⁺ : [ Ar ] 3d^4 ( n=4 ) and Fe ³⁺ : [ Ar ] 3d^5 ( n=5 ) V ³⁺ : [ Ar ] 3d^2 ( n=2 ) and Ni ²⁺ : [ Ar ] 3d^8 ( n=2 ) Mn ²⁺ : [ Ar ] 3d^5 ( n=5 ) and Co ²⁺ : [ Ar ] 3d^7 ( n=3 ) Ti ²⁺ : [ Ar ] 3d^2 ( n=2 ) and V ²⁺ : [ Ar ] 3d^3 (