# Why is helium inert, whereas hydrogen can be both reduced and oxidized?

For hydrogen and helium we fill the $1 s$ shell, which can accommodate only the TWO electrons. Now hydrogen can be reduced to give hydride anions, and can also be oxidized to give a formal ${H}^{+}$.
By contrast, helium has a FULL valence shell, i.e. $1 {s}^{2}$, which makes it extremely difficult to either reduce or oxidize. And hence helium, like the other closed-shell Noble gases, is a very unreactive customer.