What is calcium nitrite?

Calcium nitrite is an inorganic compound that is used as main raw material for cement concrete admixture, antifreezing and early strengthening agent in concrete mixing. It's also used as a corrosion inhibitor against chloride attacks, lubricating oil emulsification and heavy oil washing.

Calcium nitrite has a chemical formula Ca(NO2)2 and a molecular weight of 132.089 g/mol. It's made by reacting hydrated lime with nitrogen oxides (NOx) gas. As is the case in all nitrites, nitrogen in calcium nitrite is in a +3 oxidation state. At room temperature, calcium nitrite is an odorless white or light yellowish powder. It's also hygroscopic, well soluble in water and generates light yellow toxic solution.