Bisulfite

Not to be confused with Bisulfide or Hydrosulfite.
Equilibrium reaction relating the two tautomers of bisulfite.

The bisulfite ion (IUPAC-recommended nomenclature: hydrogensulfite) is the ion HSO−
3. Salts containing the HSO−
3 ion are also known as "sulfite lyes".[1] Sodium bisulfite is used interchangeably with sodium metabisulfite (Na2S2O5). Sodium metabisulfite dissolves in water to give a solution of Na+HSO−
3.

Na2S2O5 + H2O → 2 Na[HSO3]
  1. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.