Sodium bicarbonate

Properties

General
Name	Sodium hydrogen carbonate
Chemical formula	NaHCO3
Appearance	White solid
Physical
Formula weight	84.0 amu
Melting point	Decomposes at 543 K (270 °C)
Density	2.2 ×103 k/m3
Crystal structure	?
Solubility	10.3 g in 100g water
Thermochemistry
ΔfH0solid	-951 k/mol
S0solid	102 /mol·K
Safety
Ingestion	Safe except in very large quantities.
Inhalation	May cause irritation.
Skin	May cause irritation.
Eyes	May cause pain and redness
More info	Hazardous Chemical Database
SI units were used where possible. Unless otherwise stated, standard conditions were used. Disclaimer and references

Sodium bicarbonate (NaHCO₃), or sodium hydrogen carbonate, also known as baking soda, is a soluble white anhydrous or crystalline compound, with a slight alkaline taste resembling that of sodium carbonate. It is found in many mineral springs and also produced artificially.

It is also used as an antacid to treat acid indigestion and heartburn. The anhydrous form is also used to absorb moisture and odours—a box can be left in the refrigerator for this purpose.

Sodium bicarbonate, when exposed to a moderately strong acid, releases carbon dioxide:

• NaHCO₃ + HCl → NaCl + H₂O + CO₂ (gas)
• NaHCO₃ + CH₃COOH → CH₃COONa + H₂O + CO₂ (gas)

It is used in combination with acidic compounds as a leavening agent in baking: some forms of baking powder contain sodium bicarbonate. Formerly, it was used as a source of carbon dioxide for soda water.

See also: baking powder, sodium carbonate, list of minerals