The correct order of I.E.2 is: — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

Step 1: Consider the electronic configuration of the monovalent cations: Ne^+ is 2p5, O^+ is 2p3, F^+ is 2p4, and N^+ is 2p2. Step 2: Second ionization energy corresponds to removing an electron from these cations. Ne^+ has the highest effective nuclear charge of the period, so it has the highest IE_2. O^+ has an exceptionally stable, half-filled 2p3 subshell, making it harder to ionize than F^+. Step 3: N^+ is the easiest to ionize. Therefore, the correct decreasing order of second ionization energy is Ne > O > F > N, matching option (c).