Polar molecules are molecules wherein the atoms do not share an electron equally in a bond especially a covalent bond. Due to this unequal sharing of the electrons, a dipole would form where a part would have a partial positive charge and the other end would have a partial negative charge. Having both the partial positive and the negative charges, the molecules of the substance would have a tendency to hold each other. As a result, polar molecules would exist at room temperature as liquids or solids rather than existing as gas. Examples are water, sugar, ethanol and hydrochloric acid.