Question

Decreasing order of electron gain enthalpy of f cl br i

Answer 1

F>Cl>Br>I
Its the Decreasing order of electron gain enthalpies

Answer 2

answer :

Cl < F < Br < I

In periodic table, down in the group means from "top to bottom", the electron gain enthalpy becomes "less negative". This is because of increasing in size from F to I. "Electron gain enthalpy" is termed as the energy change when we add "electron to the valence shell" to a gaseous atom which is neutral.