Magnetic moment of the complex ion due to central metal ion is a combination of electron(s) spin and orbital interactions. 

Following is the list of some complex ions with magnetic moment (in BM) given immediately after formula of complex ion or complex

List :

$$\begin{gathered} K_4\left[Mn{\left(CN\right)}_6\right] 2.2 \\ {\left[Fe{\left(H_{2}O\right)}_6\right]}^{2+ }5.3 \\ {K}_2\left[MnC{l}_4\right] 5.9 \end{gathered}$$

Answer the following questions based on magnetic properties of 3d-transition metal ions and their complexes.