JEE Main 2021 — D And F Block Elements Question with Solution
From: JEE Main 2021 (Online) 1st September Evening Shift
Question
Identify the element for which electronic configuration in +3 oxidation state is [Ar]3d5 :
Choose an option
Show full solutionCorrect option: D
Correct answer
DFe
Step-by-step explanation
Mn(25) = [Ar]3d54s2
Mn+3 = [Ar]3d44s0
Ru-belongs to 4d transition series
Co (27) = [Ar]3d74s2
Co+3 = [Ar]3d64s0
Fe(26) = [Ar]3d64s2
Fe+3 = [Ar]3d54s0
Mn+3 = [Ar]3d44s0
Ru-belongs to 4d transition series
Co (27) = [Ar]3d74s2
Co+3 = [Ar]3d64s0
Fe(26) = [Ar]3d64s2
Fe+3 = [Ar]3d54s0
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