| − | The ''simple formula'' simply lists the elements in symbolic form, with subscripts to describe their ratio. For example, [[water]] consists of two parts [[hydrogen]] and one part [[oxygen]]. Its simple formula is, therefore, H<sub>2</sub>O, that of the basic solute of common household vinegar ([[acetic acid]]) is C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>, and that of common salt is NaCl. One usually describes an ionic compound only by a simple formula, though exceptions do exist. | + | The ''simple formula'' simply lists the elements in symbolic form, with subscripts to describe their ratio. For example, [[water]] consists of two parts [[hydrogen]] and one part [[oxygen]]. Its simple formula is, therefore, H<sub>2</sub>O, that of the basic solute of common household vinegar ([[acetic acid]]) is C<sub>2</sub>H<sub>4</sub>O<sub>2</sub> (This is often written as CH<sub>3</sub>COOH to better reflect its structure), and that of common salt is NaCl. One usually describes an ionic compound only by a simple formula, though exceptions do exist. |