Question

Atomic number of $$\mathrm{Mn},\mathrm{Fe},\mathrm{Co}$$ and Ni are 25, 26, 27 and 28 respectively. Which of the following outer orbital octahedral complexes have same number of unpaired electrons?

(i) $$[\mathrm{MnCl}{\phantom{A}}_6]{\phantom{A}}^{3-}$$

(ii) $$[\mathrm{FeF}{\phantom{A}}_6]{\phantom{A}}^{3-}$$

(iii) $$[\mathrm{CoF}{\phantom{A}}_6]{\phantom{A}}^{3-}$$

(iv) $$[\mathrm{Ni}(\mathrm{NH}{\phantom{A}}_3){\phantom{A}}_6]{\phantom{A}}^{2+}$$

Answer 1

(i) $$[\mathrm{MnCl}{\phantom{A}}_6]{\phantom{A}}^{3-}$$

(iii) $$[\mathrm{CoF}{\phantom{A}}_6]{\phantom{A}}^{3-}$$

Explanation:

$$[\mathrm{MnCl}{\phantom{A}}_6]{\phantom{A}}^{3-}:\mathrm{MN}{\phantom{A}}^{3+}(3\mathrm{d}{\phantom{A}}^4)$$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$

$$[\mathrm{CoF}{\phantom{A}}_6]{\phantom{A}}^{3-}:\mathrm{Co}{\phantom{A}}^{3+}(3\mathrm{d}{\phantom{A}}^6)$$

${\displaystyle \uparrow \downarrow }$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$

${\displaystyle \uparrow }$