Why is the bond in a hydrogen molecule nonpolar?

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Diagram showing the formation of a polar covalent bond in a water molecule, with two hydrogen atoms bonding to one oxygen atom to form H2O, illustrating shared electrons and chemical reaction. — covalent bond In polar covalent bonds, such as that between hydrogen and oxygen atoms, the electrons are not transferred from one atom to the other as they are in an ionic bond. Instead, some outer electrons merely spend more time in the vicinity of the other atom. The effect of this orbital distortion is to induce regional net charges that hold the atoms together, such as in water molecules.

The bond in a hydrogen molecule ( $H_{2}$ ) is nonpolar because it is a homonuclear bond, meaning it is formed between two identical atoms of the same element.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 a hydrogen molecule have the same electronegativity, they exert an equal pull on the shared electron pair. Consequently, the electrical charge is distributed uniformly across the bond, resulting in a dipole moment of zero.132

While there are minor ionic contributions to the bond, they are equal and opposite, causing their dipoles to cancel out and leaving the molecule electrically neutral.12