Sodium Nitrite is the inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic.It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. Other Details Formula : NaNO2 Melting Point : 271oC Molar Mass : 68.9953 g/mol Density : 2.17 g/cm³ Soluble In: Water