Why is the hydrogen-hydrogen bond nonpolar?

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Diagram showing four types of crystal bonding: ionic bonding with sodium and chlorine ions, covalent bonding with carbon atoms sharing electrons, metallic bonding with iron ions surrounded by free electrons, and molecular bonding with hydrogen molecules held by weak electrical attraction. — chemical bonding Different types of bonding in crystals.

The hydrogen-hydrogen bond ( $H_{2}$ ) is nonpolar because it is a homonuclear bond, meaning it connects two identical hydrogen atoms.12

In chemical bonding, bond polarity is determined by the relative electronegativity of the bonded atoms, which is the power of an atom to attract shared electrons toward itself. Because both atoms in an $H_{2}$ molecule are identical, they possess the same electronegativity and exert an equal pull on the shared electron pair. Consequently, the electrical charge is distributed uniformly across the bond, and the dipole moment is zero.12

While there are minor ionic contributions to the bond, they are perfectly balanced by the equal and opposite nature of the potential ionic structures, resulting in a nonpolar species.12