Co has highest standard electrode potential (M+3/M+2) among Mn,Cr,Co,Fe
∴ Complex is [Co(CN)6]4− and its splitting is as follows.

∴ electron in eg orbital is one.
JEE Main 2025 — Chemistry Inorganic Chemistry
A transition metal (M) among Mn,Cr,Co and Fe has the highest standard electrode potential (M3+/M2+). It forms a metal complex of the type [M(CN)6]4−. The number of electrons present in the eg orbital of the complex is _________.
Held on 2 Apr 2025 · Verified 6 Jul 2026.
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