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Is Sucrose Polar or Nonpolar?

Sucrose, or table sugar (C??H??O??), is one of the best-known organic compounds in the world. Sucrose is a disaccharide, which means it is two simple (six-carbon) sugars combined into one complex sugar.
Fructose and glucose (both formula C?H??O?) have their ring structures linked to each other through a single oxygen atom. Sucrose contains ether linkages and alcohol groups.

Carbon Dioxide
- Bar magnets have a north pole and a south pole. There is another kind of polarity involving electron charge-distribution in molecules. If charges either don̵7;t exist or are distributed in a canceling fashion, they cannot form poles in a molecule. If charges do exist and do not cancel, poles do exist.
  Carbon dioxide has negative ends, but the molecule has the same charge at either end. Those charges cancel. There is not a positive pole at one end and a negative pole at the other. Carbon dioxide is therefore nonpolar.
Carbon Monoxide
- Carbon monoxide, on the other hand, is negative on the oxygen and positive on the carbon. There is no charge cancellation so carbon monoxide is polar. The properties of carbon monoxide are considerably different than those of carbon dioxide.
Water
- Although water has one oxygen atom and two hydrogen atoms, the three atoms do not line up to form a straight-line segment. Water is like a mouse̵7;s head, with the oxygen being the face and the two hydrogen atoms the ears. So charge distribution is lopsided. The oxygen carries a negative charge and the hydrogen a positive charge. The end result is a negative pole on the oxygen and (by vector addition of the two positive charges) there is an equally strong positive pole between the two hydrogen atoms.
Sucrose
- Sucrose has a number of asymmetrical charge distributions. Also, the bond between the fructose and glucose portions of sucrose allows freedom of movement. Charges cannot be resolved into canceling components so sucrose is a polar molecule.
Demonstration of Polarity
- The chemist often must choose solvents to dissolve a substance in, and one of the determining factors in choosing a solvent is its polarity. The principle applies ̶0;like dissolves like.̶1; Polar substances dissolve in polar solvents. Nonpolar substances dissolve in nonpolar solvents.
  Sucrose does not dissolve in nonpolar solvents such as gasoline. Sucrose readily dissolves in the polar solvent, water. Quite a lot of it dissolves, in fact. This is empirical evidence that sucrose is, indeed, polar.

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