Which of the following electronic configurations represents a sudden large gap between the values of — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

Step 1: A sudden large gap between the second and third ionization energies (IE_3 >> IE_2) implies that the third electron is removed from a stable closed shell and the atom has exactly two valence electrons. Step 2: An electronic configuration with exactly two valence electrons has an outer configuration of ns^2. Step 3: Among the choices, option (d) has the configuration 1s2 2s2 2p6 3s2, which has exactly two outer-shell electrons. Thus, it will exhibit a sudden large gap between IE_2 and IE_3.