JEE MainChemistryd and f Block Elements
A 3d transition metal M exhibits the highest oxidation state in its series. The spin-only magnetic moment of the M ²⁺ ion in aqueous solution is :
Options
- A4.90 BM
- B5.92 BM
- C3.87 BM
- D0.00 BM
Correct answer
B. 5.92 BM
Step-by-step solution
The 3d transition metal that exhibits the highest oxidation state ( +7 ) is Manganese ( Mn ). The atomic number of Mn is 25 , and its neutral electronic configuration is [ Ar ] 4s² 3d⁵ . The divalent ion Mn ²⁺ is formed by the loss of the two 4s electrons, giving the configuration [ Ar ] 3d⁵ . The number of unpaired electrons ( n ) in Mn ²⁺ is 5 . The spin-only magnetic moment is given by = n(n+2) BM . = 5(5+2) = 35 5.92 BM . Answer: 5.92 BM