Question

The correct order of magnetic moments (spin only values in BM) among the following is (Atomic numbers: $ Mn=25,\text{ }Fe=26,\text{ }Co=27 $ )

• A. $\left[ MnCl _{4}\right]^{2-}>\left[ CoCl _{4}\right]^{2-}>\left[ Fe ( CN )_{6}\right]^{4-}$
• B. $\left[ MnCl _{4}\right]^{2-}>\left[ Fe ( CN )_{6}\right]^{4-}>\left[ CoCl _{4}\right]^{2-}$
• C. $\left[ Fe ( CN )_{6}\right]^{4-}>\left[ MnCl _{4}\right]^{2-}>\left[ CoCl _{4}\right]^{2-}$
• D. $\left[ Fe ( CN )_{6}\right]^{4-}>\left[ CoCl _{4}\right]^{2-}>\left[ MnCl _{4}\right]^{2-}$

Answer 1

Answer: (A)

As the number of unpaired electrons in the central atom increases, magnetic moment of the complex increases.


$\therefore $ The order of magnetic moments is
$[MnCl_4]^{2-} > [CoCl_4]^{2-} > [Fe(CN)_6]^{4-}$