What are dipoles in chemistry?
1 Answer
Many molecules have such dipole moments due to non-uniform distributions of positive and negative charges on the various atoms.
Explanation:
Such is the case with polar compounds like hydrogen fluoride (HF), where electron density is shared unequally between atoms.
For molecules there are three types of dipoles:
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Permanent dipoles : These occur when two atoms in a molecule have substantially different electronegativity: One atom attracts electrons more than another, becoming more negative, while the other atom becomes more positive. A molecule with a permanent dipole moment is called a polar molecule.
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Instantaneous dipoles : These occur due to chance when electrons happen to be more concentrated in one place than another in a molecule, creating a temporary dipole.
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Induced dipoles : These can occur when one molecule with a dipole repels another molecule's electrons, inducing a dipole moment in that molecule. A molecule is polarized when it carries an induced dipole.
