The electron affinity (negative electron gain enthalpy) of Group 17 elements shows a notable anomaly — p Block Elements Chemistry Question

💡 Solution & Explanation

Chlorine anomalously has a higher electron affinity than Fluorine. The 2p orbitals of Fluorine are very compact, so adding an incoming electron causes strong inter-electronic repulsions. Adding an electron to the larger 3p orbitals of Chlorine is energetically more favorable.