JEE Main · 2021 · 26 Aug 2021 · Shift 1 · p-Block Elements

Fluorine has the most positive standard reduction potential of the halogens in water, helped by its small size and large hydration energy, so ${\mathrm{F}}_2$ is the strongest oxidising agent among them. The interhalogen $\mathrm{ClF}$ hydrolyses with the more electronegative halogen leaving as halide and the less electronegative one as the hypohalous acid, giving $\mathrm{HOCl}$ and $\mathrm{HF}$. The $\mathrm{Cl}-\mathrm{F}$ bond is weaker and far more polar than the $\mathrm{Cl}-\mathrm{Cl}$ bond, so $\mathrm{ClF}$ attacks substrates more readily than $\mathrm{C}{\mathrm{l}}_2$ does, and interhalogens are in general more reactive than the halogens other than fluorine, whose own bond is exceptionally weak. The incorrect statement is that $\mathrm{C}{\mathrm{l}}_2$ is more reactive than $\mathrm{ClF}$.