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Why is water polar even though it has two oxygen-hydrogen bonds?

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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 water molecule is polar because of its specific molecular geometry and the nature of its covalent bonds.

While each oxygen-hydrogen bond is polar due to the higher electronegativity of the oxygen atom—which draws shared electrons toward itself, creating partial negative and positive charges—the overall polarity of a molecule depends on its shape.12

In some molecules, such as carbon dioxide, polar bonds are arranged linearly, causing their individual dipole moments to cancel each other out, resulting in a nonpolar molecule. In contrast, the water molecule is bent or angular, with the two hydrogen atoms bound to the oxygen atom at an angle of 104.5°. Because of this angular structure, the bond dipole moments do not cancel out, leaving the molecule with a nonzero net electric dipole moment.132