Question:
The electron gain enthalpy (in $\mathrm{kj} / \mathrm{mol}$ ) of fluorine, chlorine, bromine and iodine, respectively, are:
Correct Option: , 3
Solution:
Chlorine has highest electron gain enthalpy (most negative) among the given elements, the electron gain enthalpy decreases down the group i.e., moves to least negative.