* H2 is a molecule, not an atom. It's formed by two hydrogen atoms bonding together.

* Valence electrons are associated with individual atoms.

Here's how to think about it:

* Each hydrogen atom has 1 valence electron. This is because hydrogen is in the first column of the periodic table, and elements in the first column have one electron in their outer shell.

* When two hydrogen atoms bond, they share their valence electrons. This forms a covalent bond, creating the H2 molecule.

Therefore, while each hydrogen atom has 1 valence electron, the H2 molecule has a total of 2 valence electrons involved in the bond.