Sucrose is a polar molecule because the bond between the oxygen and the hydrogen atoms gives the oxygen a slight negative charge and the hydrogen a slight positive charge. The negative and positive areas attract the polar water molecules, and this allows the sucrose to dissolve in water.
A polar molecule can be identified because it will always have a partial positive and partial negative charge as a result of the polar bonds that are arranged asymmetrically. Water is another example of a polar molecule. In contrast, a nonpolar molecule is one where there is an equal sharing of electrons between the two atoms of a diatomic molecule.