| − | Substances in which at least one atom has an imbalance of protons and electrons.<ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref>
| + | Either a single [[atom]] or a group of atoms that has an imbalance of [[proton|protons]] and [[electron|electrons]], resulting in a positive or negative charge. <ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref> |