Q. Identify the coordination complexes in which the central metal ion has $d^4$ configuration. (A) $[\mathrm{FeO_4}]^{2-}$ (B) $[\mathrm{Mn(CN)_6}]^{3-}$ (C) $[\mathrm{Fe(CN)_6}]^{3-}$ (D) $\mathrm{Cr_2(O-C(=O)-Me)_4(H_2O)_2}$ (E) $[\mathrm{NiF_6}]^{2-}$. Choose the correct answer from the options given below :
A) (B), (C) and (D) only
B) (C) and (E) only
C) (B) and (D) only
D) (A), (B) and (E) only
Explanation
[Solution by Dr. Abubacker] (A) Fe(+6): d². (B) Mn(+3): d⁴. (C) Fe(+3): d⁵. (D) chromium(II) acetate hydrate, Cr(+2): d⁴. (E) Ni(+4): d⁶. So (B) and (D) have d⁴. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.