Question

why oxygen has less negative electron gain enthalpy than sulphur

Answer 1

The oxygen has less negative gain enthalpy than sulphur.Because the atomic number of oxygen is 8. And the atomic number of sulphur is 16. The oxygen has only have strength to gain two electrons.The sulphur has strength to gain three electrons.This is the reason for that the oxygen has less negative electron gain enthalpy than sulphur.