Sodium Metabisulfite
Synonyms: Sodium metabisulphite; Disulfurous acid, disodium salt; Sodium Metabisulfite; Disodium disulphite; Pyrosulfurous acid, disodium salt.
Free flowing, white, fine granular crystal having a characteristic odor of sulfur dioxide and is soluble in water
USES:
Sterilization in many processes
Photography
Winemaking (Sterilization)
Tanning hides
INCI Name, CAS No., etc.
INCI Name: Sodium MetabisulfiteCAS No.: 7681-57-4
Formula: Na2S2O5
Molecular Weight: 190.11
pH of 5% Solution: 4.3
Bulk Density, lb/ft3: 86
Specifications
Appearance White Crystals
Arsenic (As) 0.0 – 1.0 ppm
Sodium Metabisulfite (Na2S2O5) 98.6 - 99.8 %
Chloride (Cl) 0.0 - 0.02 %
Heavy Metals (as Pb) 0.0 – 10.0 ppm
Identification To Pass Tests
Insoluble Matter (Ca, Mg, NH4OH ppt) 0.0 - 0.05 %
Iron (Fe) 0.0 – 5.0 ppm
Lead (Pb) 0.0 - 0.5 ppm
pH (5% solution) 4.0 - 4.6
Reaction to Amm Silver Nitrate To Pass Test
Selenium (Se) 0.0 – 5.0 ppm
Sodium Sulfite (Na2SO3) 0.0 - 0.6 %
Sodium Thiosulfate (Na2S2O3) 0.0 - 0.04 %
Sulfur Dioxide (SO2) 66.4 – 67.2 %
Safety Data Sheet

Technical Data Sheet
