Dissociation

Dissociation is the process by which a molecule separates into ions. It may also be called ionization, but because there are other ways to form ions, the term dissociation is preferred. Substances dissociate to different degrees, ranging from substances that dissociate very slightly, such as water, to those that dissociate almost completely, such as strong acids and bases. The extent to which a substance dissociates is directly related to its ability to conduct an electric current. A substance that dissociates only slightly (as in the case of a weak acid like vinegar) is a weak electrolyte, as it conducts electricity poorly. A substance that is almost completely dissociated (such as table salt, NaCl, or hydrochloric acid, HCl) conducts electricity very well. The ability to conduct electricity is based on the ionic makeup of a substance. The more ions a substance contains, the better it will conduct electricity.