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QAIPMT-2005-Ch-2519: NEET 2005 Chemistry - Class 12 AIPMT-2005-Ch-2519 Solution: Four successive members of the first row transition elements…
Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionisation enthalpy?
Multiple Choice Options
- A Vanadium (Z = 23)
- B Chromium (Z = 24)
- C Manganese (Z = 25)
- D Iron (Z = 26)
Step-by-Step Verified Solution
For third ionization enthalpy electronic
configuration of
V 2+ (21) : [Ar] 18 3d 3 4s 0
Cr 2+ (22) : [Ar] 18 3d 4 4s 0
Mn 2+ (23) : [Ar] 18 3d 5 4s 0
Fe 2+ (24) : [Ar] 18 3d 5 4s 1
Mn has most stable configuration due to half
filled d-orbital. Hence 3rd ionization energy will
be highest for Mn.