Positively charged ions are attracted to negatively charged ions. Sodium and chloride ions combine to form sodium chloride, common table salt, through the formation of ionic bonds. Ionic compounds are readily dissociated in aqueous solution, releasing their charged ions. Hydrogen bonds Hydrogen bonds are the third major category of chemical bonds. Like ionic bonds, they are electrostatic interactions between regions of opposite charge.
Hydrogen bonds form between areas of unlike charge in polarized bonds.
In water, for example, each molecule has two polarized bonds. The positively charged 'hydrogen end' of one water molecule is electrostatically attracted to the negatively charged 'oxygen end' of another water molecule, forming a hydrogen bond between the two molecules. Each water molecule can enter as many as four hydrogen bonds with other molecules. Hydrogen bonds are typically indicated by dotted lines. Hydrogen bonds are considered to be weak and easily broken bonds.