Final answer:
A water molecule is polar because of the difference in electronegativity between the oxygen and hydrogens.
Step-by-step explanation:
A water molecule is polar because of the difference in electronegativity between the oxygen and hydrogens. Oxygen is more electronegative than hydrogen, meaning it has a stronger pull on the shared electrons in the molecule. This causes the oxygen atom to be slightly negative and the hydrogen atoms to be slightly positive, giving the molecule an overall dipole moment.
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