• # question_answer In nitroprusside ion, the iron and $NO$ exist as $F{{e}^{II}}$ and $N{{O}^{+}}$ rather than $F{{e}^{III}}$ and $NO$. These forms can be differentiated by [IIT-JEE 1998] A) Estimating the concentration of iron B) Measuring the concentration of $C{{N}^{-}}$ C) Measuring the solid state magnetic moment D) Thermally decomposing the compound

The existence of $F{{e}^{2+}}$ and $N{{O}^{+}}$ in Ntroprusside ion ${{[Fe{{(CN)}_{5}}NO]}^{2-}}$ can be established by measuring the magnetic moment of the solid compound which should correspond to $(F{{e}^{2+}}=3{{d}^{6}})$ four unpaired electrons.