How does bond polarity create an electric dipole?

Bond polarity creates an electric dipole through the unequal distribution of electrical charge between atoms in a chemical bond.1

This process is driven by differences in electronegativity, which is an atom's ability to attract shared electrons toward itself. When two atoms with different electronegativities form a covalent bond, the more electronegative atom pulls the shared electron pair closer, acquiring a partial negative charge. Conversely, the less electronegative atom loses its equal share of the electron pair, resulting in a partial positive charge.1

The existence of these equal but opposite partial charges at the ends of a bond creates an electric dipole. The magnitude of this dipole is measured by the dipole moment, defined as the product of the magnitude of the partial charges and the distance separating them. While individual bonds may be polar, whether a polyatomic molecule as a whole acts as a permanent dipole depends on its geometric shape; if the bond dipoles are arranged symmetrically, they may cancel each other out, resulting in a nonpolar molecule.12