Meta- (chemistry)

In chemistry, meta is a prefix, used for systematic names in IUPAC nomenclature. It has several meanings.


 * In organic chemistry, meta indicates the positions of substituents in aromatic cyclic compounds. The substituents have the 1,3-positions, for example in resorcinol.


 * Meta may also denote the dehydrated form of an acid, salt or organic derivative in a series.
 * For example metabisulfite:
 * 2 bisulfite (HSO3−) → 1 metabisulfite S2O52&minus; + H2O
 * and metaphosphoric acid:
 * 3 orthophosphoric acid H3PO4 → 1 trimetaphosphoric acid (H3P3O9) + 3 H2O.


 * Meta-antimonic acid, the dehydrated form of antimonic acid (H3SbO4), is HSbO3.