\(K _{3}\left[ Fe ( CN )_{6}\right]\) has more value of \(\Delta_{0}\) than that of \(\left[ Co \left( NH _{3}\right)_{6}\right] Cl _{3} ;\) as \(\overline{ CN }\) is stronger ligand.
More \(\Delta_{0} \Rightarrow\) smaller value of absorbed \(\lambda\)
Spin only magnetic moment \((\mu)=\sqrt{3} \,BM\)
\(=1.732 \,BM\)
Rounding off \(\Rightarrow 2\)
પરમાણુ ભાર : $Mn = 25,\,Fe = 26,\,Co = 27,\,Ni = 28$