Why are halogens strong oxidising agents ?

Explanation

Due to low bonds dissociation enthalpy, high electronegativity and large negative electron gain enthalpy halogens have a strong tendency to accept electrons and thus get reduced.
`X_(2) + 2 e^(-) rarr 2 X^(-)`
As a result, halogens act as strong oxidising agents. Their oxidising power, however, decreases from `F_(2)` to `I_(2)` as is evident from their electrode potentials :
`E^(@)._(F_(2)//F^(-))=+2.87 V, E^(@)._(Cl_(2)//Cl^(-)) = + 1.36 V" ,"" "E_(Br_(2)//Br^(-))=+1.09 V and E_(I_(2)//I^(-)) = + 0.54 V`
Thus, `F_(2)` is the strongest while `I_(2)` is the weakest oxidising agent.