What is Sodium Metabisulfite?
Sodium Metabisulfite has the chemical formula Na2S2O5 and its molecular mass is 190.107g/mol.It is a well-known antioxidant being used in pharmaceuticals or Sodium pyrosulfite. It is white in color and solid powder form. It is a sulfur-containing ionic compound of sodium. Sodium has a positive charge while metabisulfite (S2O52-) has a negative charge. It is called Metabisulfite due to the presence of two S atoms. Meta term refers to the direct bond present between two S atoms. It is also known as sodium pyrosulfate and sodium disulfate. .
How sodium metabisulfite made ?
Sodium pyrosulfite can be prepared by treating a solution of sodium hydroxide with sulfur dioxide.
Physical Properties of product
- It is white in color, solid, and in powder form.
- It has a similar odor to Sulfur dioxide.
- The molar mass of sodium metabisulfite is 190.107 g/mol.
- It has a melting point of 1800C, but it decomposes around 1500C.
- On boiling, It decomposes readily.
Chemical Properties of product
- sodium metabisulfite pH is maintained at 4.6 while preparing the solution. So, it is acidic in nature.
- It is non-combustible in nature. When heated at high temperature, it releases toxic flames of oxides of sulfur
- When it is mixed in water, it releases sulfur dioxide. It is very harmful to the lungs. It has a pungent strong smell.
- When it is treated with strong acids, it releases SO2. The reaction is shown below:
- 2HCL + Na2S2O5 ⇌ 2SO2 + 2NaCl + H2O
What is sodium metabisulfite used for?
Sodium metabisulphite is used as an antioxidant agent in many pharmaceutical formulations. It is extensively used as a food preservative and disinfectant.
- It acts as a reducing agent in the dough, it helps in making batter softer, easier to knead.
- It is a well-known antioxidant used in pharmaceuticals.
- It is helpful in tests of sickle cell anemia.
- It is used in industries as a corrosion inhibitor because it is an oxygen scavenger.
- It is used in wastewater treatment as it is a good reducing agent.
- It is used as a sanitizing ingredient, to clean the tools of winemaking.
Shipping and packing Sodium pyrosulfite
It packed in plastic woven bags lined with polyethylene plastic bags, bags of 25 kg or 50 kg net each. Should be stored in a cool, dry warehouse, packing seal, should prevent air oxidation.