Carbonyl compounds water and

The Dipole Moment. A dipole results from the presence of an unsymmetrical distribution of electron density within a molecule, due either to a formal charge separation, such as in amino acids, or due to differences in the electronegativities of the atoms forming a covalent bond, as in carbonyl compounds, water, and alcohols. An isolated, neutral atom, of course, cannot have an unsymmetrical electron distribution therefore atoms cannot be dipolar in nature. That is not to say, of course, that they cannot be polarized, or have their electron cloud distorted by an external electric field, but that subject is considered later. The dipole momenl, of a molecule is defined as... 

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