The incorrect relationship in the following pair in relation... | Chemistry - Periodicity & Ionization Enthalpy | SolveeIt | Solveeit

Today, August 19

Question

The incorrect relationship in the following pair in relation to ionization enthalpy is :

Visual representation for Chemistry

A

Mn $^+$ < Mn $^{+2}$

B

Mn $^+$ < Fe $^{+2}$

C

Fe $^{+2}$ < Fe $^{+3}$

D

Mn $^+$ < Cr $^+$

Answer

Mn $^+$ < Cr $^+$

Explanation

Solution

Successive ionization energies increase; isoelectronic ions with higher nuclear charge have higher ionization enthalpy. Mn $^+$ has a higher charge (25 protons) than Cr $^+$ (24 protons) for the same electron count, so its ionization enthalpy is higher. Therefore, option (4) is wrong.