Question

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 ionization
enthalpy?
(a) Vanadium (Z = 23)
(b) Chromium (Z = 24)
(c) Manganese (Z = 25)
(d) Iron (Z = 26)

Answer 1

YOUR ANSWER IS C OPTION

Third electron which is removed in third ionisation enthalpy belongs to 3d-subshells. It means in all elements, shell and subshells are same therefore, required amount of energy is based upon stability of d-subshell. Hence, Mn shows highest third ionisation energy.