A polar molecule is a molecule in which the individual atoms have an uneven distribution of electron density, resulting in the molecule having a positive and negative end or pole. This uneven distribution is typically due to differences in electronegativity between the atoms. Water (H2O) is a good example of a polar molecule. The oxygen atom is more electronegative than the hydrogen atoms, so it attracts the shared electrons more strongly, resulting in a partial negative charge on the oxygen atom and partial positive charges on the hydrogen atoms. This gives water its characteristic bent shape and allows it to form hydrogen bonds with other polar molecules.
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