For a tetrahedral complex [ M C l ₄ ]²⁻ , the spin-only magnetic moment is 3.83 ~B .M. The element M is -

Step-by-step solution

[ MCl ₄ ]²⁻ Tetrahedral = sp ³ hybridisation M ⁺² = n ( n +2) B M .=3.83 n =3 Means configuration of M ⁺²=3 ~d ⁷ so, M=3 d⁷ 4 s²= ₂₇ C o