Sodium Hydrogen Carbonate

Sodium bicarbonate is a white solid that is crystalline, but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate).pH (of freshly prepared 0.1 molar aqueous solution): 8.3 at 77 °F. pH (of saturated solution): 8-9.

Na2CO3 + CO2 + H2O → 2 NaHCO3

If kept cool (room temperature) and dry (an airtight container is recommended to keep out moist air), sodium hydrogen carbonate can be kept without a significant amount of decomposition for at least two or three years.