Question

Fluorine shows only $+1$, $-1$ oxidation state while other halogen element shows $+3$, $+5$ and $+7$ oxidation states in addition to $+1$, $-1$. Why?

Answer 1

Fluorine is the most electronegative element of the periodic table. It always exhibits $-1$ and $+1$ oxidation state but other halogens show $-1$, $+1$, $+3$, $+5$ and $+7$ oxidation states. They show a high oxidation state in the presence of vacant $d$-orbital. But fluorine has no vacant $d$-orbital so it does not show a high oxidation state.