Registration Dossier

Diss Factsheets

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Sodium bicarbonate is a white odourless solid with relative density of 2.21 -2.23 at 20 ˚C, which decomposes when heated above 50 ˚C with the release of CO2, H2O and Na2CO3, resulting in total decomposition at 270 ˚C. Its solubility in water is 93.4 g/L at 20 ˚C and pH 8.4. In aqueous solution, sodium bicarbonate undergoes a complete dissociation into the respective ions. Its solubility in most organic solvents is negligible. The n-octanol/water partition coefficient is not applicable because the substance is inorganic. The vapour pressure cannot be determined experimentally (decomposition when heated) but it is negligible because sodium bicarbonate is an inorganic solid.

Based on its structure and the lack of chemical groups associated with explosive and/or oxidizing properties, sodium bicarbonate is considered to be non-explosive and non-oxidizing. Based on the experience in manufacture and handling, the substance is known not to react with water and not to possess pyrophoric properties. In a standard flammability test, no propagation of combustion occurred, indicating that sodium bicarbonate is non-flammable.

Particle size distribution measurements have been performed on 3 different samples of sodium bicarbonate. Mass median aerodynamic diameters were 53, 406 and 563 μm, while the D90 varied from 81 to 551 μm.