Dipoles and Dipole Moments: The Link to Polarity
Hydrocholoric acid is an example of a polar compound because there is only one lone dipole, pointing right. There is no balancing dipole pointing left. Therefore, it is assumed that the electronegativity for the chloride ion goes unchecked and there is an overall dipole moment.
Water follows the same premise. Both dipoles are pointing towards the more electronegative oxygen atom, which also has two pairs of non- bonding electrons, further throwing off the balance of charge distribution in the compound. Hence, we gain see a dipole moment and water as a polar substance.
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