Question

cl have more negative electron gain enthalpy than f account it

Answer 1

F- can be form easily than Cl becuse of its small atomic size.And F- is more stable than Cl-.

Answer 2

Answer:

Due to its small size, the electron–electron repulsions in the relatively compact 2p-sub-shell are comparatively large, and hence, the incoming electron is not accepted with the same ease as is the case with larger Cl atom. Consequently, electron gain enthalpy of Cl is more negative than that of F.