Considering the parameters such as bond dissociation enthalpy, electron gain enthalpy and hydration enthalpy, compare the oxidising power of F_(2) and Cl_(2).

Considering the parameters such as bond dissociation enthalpy, electro

1.	Considering the parameters such as bond dissociation enthalpy, electron gain enthalpy and hydration enthalpy, compare the oxidising power of F_(2) and Cl_(2).
Answer» Solution :The etectrode potential of `F_(2)` (+2.87 V) is much HIGHER that of `Cl_(2)` (+1.36 V), therefore, `F_(2)` is a much stronger OXIDISING agent than `Cl_(2)`. Now, electrode potential depends UPON three factors : (i) bond dissociationn energy, (ii) electron gain enthalpy and (iii) hydration energy. ALTHOUGH electron gain enthalpy of fluorine is LESS negative (-333 kJ `mol^(-1)`) than that of chlorine (-349 kJ `mol^(-1)`), the bond dissociationn energy of F-F bond is much lower (158.8 kJ `mol^(-1)`) than that of Cl-Cl bond (242.6 kJ `mol^(-1)`) and hydration energy of `F^(-)` ion (515 kJ `mol^(-1)`) is much higher than that of `Cl^(-)` ion (381 kJ `mol^(-1)`). The later two factors more than compensate the less negative electron gain enthalpy of `F_(2)`. As a result, electrode potential of `F_(2)` is higher than that of `Cl_(2)` and hence `F_(2)` is a much stronger oxidising agent than `Cl_(2)`.