Among Co 3 + , Ti 2 + , V 2 + and Cr 2 + ions, one if used as a reagent cannot liberate H 2 from dilute mineral acid solution, its spin-only magnetic moment in gaseous state is _____ B.M. (Nearest integer)

Step-by-step solution

Among the given species Co 3 + cannot undergo oxidation, hence, Co 3 + can't liberate H 2 . It has d 6 configuration, Number of unpaired electrons = 4 μ = n n + 2 B . M μ = 4 × 6 = 4 . 92   B . M .