One thing that the shape of a molecule can affect is its polarity. Polarity refers to the distribution of electrical charge within a molecule. A molecule is polar if it has a positive end and a negative end. The shape of a molecule can determine whether or not it is polar. For example, a linear molecule, such as carbon dioxide, is nonpolar because the positive and negative charges are evenly distributed throughout the molecule. However, a bent molecule, such as water, is polar because the oxygen atom is more electronegative than the hydrogen atoms, which causes the molecule to have a positive end and a negative end.