Naming oxyanions and oxyacids
The IUPAC process for naming an oxyanion is defined by how much oxygen is bound to the central atom compared to the amount of oxygen that could be bound. We add a prefix and suffix to the root of the element name to indicate this.
Table 1: Table showing the relevant prefixes, suffixes for oxyanion and oxyacid naming.
For example, the chlorine oxyanion (ClO4-) cannot have more oxygen bound to the central atom. It is, therefore, in the final column of Table 1 and so we take the chlor- root and add the prefix, per, and the suffix, -ate.
Hence, ClO4- is called perchlorate.