Sodium bicarbonate

Properties

General

Name Sodium hydrogen carbonate
Chemical formula Na HCO₃
Appearance White solid

Physical

Formula weight 84.0 amu
Melting point Decomposes at 543 K (270 °C)
Density 2.2 ×10³ kg/m³
Crystal structure ?
Solubility 10.3 g in 100g water

Thermochemistry

Δ_fH⁰_solid -951 kJ/mol
S⁰_solid 102 J/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 (Na HCO₃), 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.

**Properties**
General
Name	Sodium hydrogen carbonate
Chemical formula	Na HCO₃
Appearance	White solid
Physical
Formula weight	84.0 amu
Melting point	Decomposes at 543 K (270 °C)
Density	2.2 ×10³ kg/m³
Crystal structure	?
Solubility	10.3 g in 100g water
Thermochemistry
Δ_fH⁰_solid	-951 kJ/mol
S⁰_solid	102 J/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

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.