Which of the following gaseous species have an exceptionally LOW (near zero) or POSITIVE electron af — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

Electron affinity approaches zero or becomes negative (meaning positive $\Delta_{eg}H$) when adding an electron disrupts a highly stable state. Noble gases have fully filled shells. Alkaline earth metals have fully filled $s$ -subshells. The Nitrogen family has stable, exactly half-filled $p$ -subshells. Halogens, conversely, have the highest electron affinities as they are one electron short of a noble gas core.