heteronuclear molecule

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July 22, 2026

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A heteronuclear molecule is a molecule composed of different nuclei. This means the atoms within the molecule are of different elements. For example, hydrogen chloride (HCl) is a heteronuclear molecule because it contains both hydrogen and chlorine atoms.123

In contrast, homonuclear molecules are made up of identical nuclei, meaning all atoms in the molecule are the same element, such as oxygen (O₂). The bonds in heteronuclear molecules can be polar covalent or ionic, depending on the electronegativity difference between the atoms. This difference in electronegativity leads to an unequal distribution of electrical charge, creating partial positive and negative charges on the atoms.3452

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…at each end of a heteronuclear bond (i.e., a bond between atoms of different elements) gives rise to an electric dipole. The magnitude of this dipole is expressed by the value of its dipole moment, μ, which is the product of the magnitude of the partial charges times their separation…
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…at each end of a heteronuclear bond (i.e., a bond between atoms of different elements) gives rise to an electric dipole. The magnitude of this dipole is expressed by the value of its dipole moment, μ, which is the product of the magnitude of the partial charges times their separation…
Read More