Sulfites are added to wine as a preservative by either bubbling sulphur dioxide gas in the wine or adding potassium metabisulfite. Both are readily soluble in wine. The sulfur dioxide (SO2) gas equilibrates between Sulfur dioxide (SO2) + water (H2O) and hydrogen ions (H+) + Bisulfite ion (HSO3-). As the pH decreases the fraction of total sulfite present as the bisulfite ion increases so that at pH4 (wine has a pH range of 3-4) the bisulfite ion is the predominant species present in the wine. The bisulfite ion also exists in equilibrium with hydrogen ion (H+) + sulfite ion (SO3 2-). Similarly, the addition of potassium metabisulfite to wine creates an equilibrium of bisulfite and sulfite ions along with free potassium ions (K+). Addition of a scientifically tested, very specific measurement of hydrogen peroxide (H2O2) oxidizes the bisulfite ion (HSO3-) to the bisulfate ion (HSO4-) and water which is then further converted to the sulfate ion (SO4-) plus water.