Description
Sodium bicarbonate (IUPAC name: sodium hydrogen carbonate) is a chemical compound with the formula NaHCO3. It is a salt composed of sodium ions and bicarbonate ions. 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). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. It is among the food additives encoded by the European Union, identified as E 500. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, the names sodium bicarbonate and bicarbonate of soda are often truncated. Forms such as sodium bicarb, bicarb soda, bicarbonate, bicarb, or even bica are common. The word saleratus, from Latin sal æratus meaning “aerated salt”, was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate.The prefix “bi” in “bicarbonate” comes from an outdated naming system and is based on the observation that there is twice as much carbonate (CO3) per sodium in sodium bicarbonate (NaHCO3) as there is carbonate per sodium in sodium carbonate (Na2CO3) and other carbonates. The modern way of analyzing the situation based on the exact chemical composition (which was unknown when the name “sodium bicarbonate” was coined) says this the other way around: there is half as much sodium in NaHCO3 as in Na2CO3 (Na versus Na2).
Synonyms
Carbonic acid monosodium salt;Sodium Hydrogen Carbonate;Sodium hydrogencarbonate;Sodium hydrogenocarbonate;sobatum
IUPAC Name
sodium; hydrogen carbonate
Molecular Weight
84
Molecular Formula
CHNaO3
Canonical SMILES
C(=O)(O)[O-].[Na+]
InChI
InChI=1S/CH₂O3.Na/c2-1(3)4;/h(H2,2,3,4);/q;+1/p-1
InChI Key
UIIMBOGNXHQVGW-UHFFFAOYSA-M
Boiling Point
851°C
Melting Point
270ºC
Flash Point
169.8ºC
Density
2.159
Solubility
1 in 10 % at 77° F (NTP, 1992);Soluble in water. Insoluble in ethanol;In water, 10.3 g/100 g water at 25 °C;Soluble in 10 parts water at 25 °C; 12 parts water at about 18 °C;Solubility in water = 6.4, 7.6, 8.7, 10.0, 11.3, 12.7, 14.2, 16.5, and 19.1 g/100g solution at 0, 10, 20, 30, 40, 50, 60, 80, and 100 °C, respectively; Solubility in water = 6.9, 8.2, 9.6, 11.1, 12.7, 14.5, 16.5, 19.7, and 23.6 g/100g H₂O at 0, 10, 20, 30, 40, 50, 60, 80, and 100 °C, respectively. Solubility is lower in the presence of sodium carbonate;Insoluble in ethanol;Solubility in water, g/100ml at 20 °C: 8.7
Appearance
White powder or superfime crystal
Color Form
White, monoclinic prisms;White crystalline powder or granules;White powder or crystalline lumps
Complexity
33.9
Covalently-Bonded Unit Count
2
Decomposition
Hazardous decomposition products formed under fire conditions: Carbon oxides, sodium oxides.;When heated to decomposition it emits acrid smoke, fumes, and carbon dioxide.;Sodium bicarbonate starts decomposing when heated over 50 °C, releasing CO2, H₂O and Na2CO3, with total decomposition at 270 °C.;50 °C
EC Number
205-633-8
Exact Mass
83.9823
Formal Charge
0
H-Bond Acceptor
3
H-Bond Donor
1
Heavy Atom Count
5
ICSC Number
1044
LogP
-1.11230
MDL Number
MFCD00003528
MeSH Entry Terms
Baking Soda;Bicarbonate, Sodium;Carbonic Acid Monosodium Salt;Hydrogen Carbonate, Sodium;Soda, Baking;Sodium Bicarbonate;Sodium Hydrogen Carbonate
Monoisotopic Mass
83.9823
Odor
Odorless
Other Experimental
Begins to lose carbon dioxide at about 50 °C and at 100 °C it is converted to sodium carbonate.;Stable in dry air, but slowly decomposes in moist air;MP: 60 °C. Solubility: in water, 7.8 g/100g at 18 °C;Solution of 1.3% is approximately isotonic with body fluids;Readily decomposed by weak acids; in aqueous solution it begins to break up into carbon dioxide and sodium carbonate at about 20 °C and completely on boiling;Alkalinity increase as solutions stand, are agitated, or heated; in liquid mixtures containing bismuth subnitrate, sodium bicarbonate reacts with acid formed by hydrolysis of bismuth salt;1 g neutralizes approximately 120 mL of 0.1 N hydrochloric acid;Specific heat capacity = 87.7 kJ/mol-K at 25 °C;Enthalpy of solution = -18 kJ/mol;Dielectric constant = 4.39 debyes at 25 °C
Physical State
White crystalline powder or granules
Refractive Index
1.5
Rotatable Bond Count
0
RTECS Number
VZ0950000
Stability
Stable.
Symbol
GHS07
UNII
8MDF5V39QO
Vapor Pressure
2.58E-05mmHg at 25°C
