# What is the oxidation number of fluorine in HF?

We got $\stackrel{- I}{F}$
Fluorine is the most electronegative atom in the entire Periodic Table, so it always gets assigned the other electron in the covalent bond of $H - F$ to give $\stackrel{- I}{F}$ and $\stackrel{+ I}{H}$. What are the oxidation numbers of oxygen and fluorine in the (real) molecule, $O {F}_{2}$?