Not to be confused with carbolic acid or carboxylic acid.
Carbonic acid
Names
IUPAC name
Carbonic acid[1]
Other names
Oxidocarboxylic acid
Hydroxyformic acid
Hydroxymethanoic acid
Carbonylic acid
Hydroxycarboxylic acid
Dihydroxycarbonyl
Carbon dioxide solution
Aerial acid
Metacarbonic acid
Identifiers
CAS Number
463-79-6Y
3D model (JSmol)
Interactive image
ChEBI
CHEBI:28976Y
ChEMBL
ChEMBL1161632Y
ChemSpider
747Y
DrugBank
DB14531
ECHA InfoCard
100.133.015
EC Number
610-295-3
Gmelin Reference
25554
KEGG
C01353Y
PubChem CID
767
UNII
142M471B3JY
CompTox Dashboard (EPA)
DTXSID9043801
InChI
InChI=1S/CH2O3/c2-1(3)4/h(H2,2,3,4)Y
Key: BVKZGUZCCUSVTD-UHFFFAOYSA-NY
InChI=1/H2O3/c2-1(3)4/h(H2,2,3,4)
Key: BVKZGUZCCUSVTD-UHFFFAOYAU
SMILES
O=C(O)O
Properties
Chemical formula
H 2CO 3
Appearance
Colorless gas
Melting point
−53 °C (−63 °F; 220 K)[2] (sublimes)
Boiling point
127 °C (261 °F; 400 K) (decomposes)
Solubility in water
Reacts to form carbon dioxide and water
Acidity (pKa)
pKa1 = 3.6 at 25 °C pKa2 = 10.329
Conjugate base
Bicarbonate, carbonate
Hazards
NFPA 704 (fire diamond)
0
0
1
Structure
Crystal structure
monoclinic
Space group
p21/c, No. 14
Point group
-
Lattice constant
a = 5.392 Å, b = 6.661 Å, c = 5.690 Å
α = 90°, β = 92.66°, γ = 90°[3]
(D 2CO 3 at 1.85 GPa, 298 K)
Lattice volume (V)
204.12 Å3
Formula units (Z)
4 formula per cell
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Chemical compound
Carbonic acid is a chemical compound with the chemical formula H2CO3. The molecule rapidly converts to water and carbon dioxide in the presence of water. However, in the absence of water, it is (contrary to popular belief) quite stable at room temperature.[4][5] The interconversion of carbon dioxide and carbonic acid is related to the breathing cycle of animals and the acidification of natural waters.[3]
In biochemistry and physiology, the name "carbonic acid" is sometimes applied to aqueous solutions of carbon dioxide. These chemical species play an important role in the bicarbonate buffer system, used to maintain acid–base homeostasis.[6]
^"Front Matter". Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. pp. P001–4. doi:10.1039/9781849733069-FP001. ISBN 978-0-85404-182-4.
^W. Hage, K. R. Liedl; Liedl, E.; Hallbrucker, A; Mayer, E (1998). "Carbonic Acid in the Gas Phase and Its Astrophysical Relevance". Science. 279 (5355): 1332–5. Bibcode:1998Sci...279.1332H. doi:10.1126/science.279.5355.1332. PMID 9478889.
^ abBenz, Sebastian; Chen, Da; Möller, Andreas; Hofmann, Michael; Schnieders, David; Dronskowski, Richard (September 2022). "The Crystal Structure of Carbonic Acid". Inorganics. 10 (9): 132. doi:10.3390/inorganics10090132. ISSN 2304-6740.
^Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 310. ISBN 978-0-08-037941-8.
^Loerting, Thomas; Tautermann, Christofer; Kroemer, Romano T.; Kohl, Ingrid; Hallbrucker, Andreas; Mayer, Erwin; Liedl, Klaus R.; Loerting, Thomas; Tautermann, Christofer; Kohl, Ingrid; Hallbrucker, Andreas; Erwin, Mayer; Liedl, Klaus R. (2000). "On the Surprising Kinetic Stability of Carbonic Acid (H2CO3)". Angewandte Chemie International Edition. 39 (5): 891–4. doi:10.1002/(SICI)1521-3773(20000303)39:5<891::AID-ANIE891>3.0.CO;2-E. PMID 10760883.
^Acid-Base Physiology 2.1 – Acid-Base Balance by Kerry Brandis.
Carbonicacid is a chemical compound with the chemical formula H2CO3. The molecule rapidly converts to water and carbon dioxide in the presence of water...
water and the dissociated ions of carbonicacid (i.e. bicarbonate and hydrogen ions). The active site of most carbonic anhydrases contains a zinc ion. They...
diatomic molecules. Carbon dioxide is soluble in water, in which it reversibly forms H2CO3 (carbonicacid), which is a weak acid, because its ionization...
+ NaHCO3 → NaCl + H2CO3 The carbonicacid rapidly equilibrates with carbon dioxide and water through catalysis by carbonic anhydrase enzymes bound to the...
buffer system is an acid-base homeostatic mechanism involving the balance of carbonicacid (H2CO3), bicarbonate ion (HCO− 3), and carbon dioxide (CO2) in...
Carbonation is the chemical reaction of carbon dioxide to give carbonates, bicarbonates, and carbonicacid. In chemistry, the term is sometimes used in...
bicarbonate Calcium bicarbonate Ammonium bicarbonate CarbonicacidCarbon dioxide Carbonate Carbonic anhydrase Hard water Arterial blood gas test "hydrogencarbonate...
A carbonate is a salt of carbonicacid, H2CO3, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word "carbonate"...
acid and other fruit acids, predicted to have an impact on human teeth. Carbon dioxide gas dissolved in water creates a small amount of carbonicacid...
acid is used in day-to-day life as vinegar. Citric acid is used as a preservative in sauces and pickles. Carbonicacid is one of the most common acid...
can be thought of chemically as the double acyl chloride analog of carbonicacid, or structurally as formaldehyde with the hydrogen atoms replaced by...
acid anhydride refers to an acidic oxide, an oxide that reacts with water to form an oxyacid (an inorganic acid that contains oxygen or carbonicacid)...
of carbon monoxide as it was based on diamond, graphite, coal and carbonicacid) Carbonate was defined as "a compound formed by the union of carbonic acid...
Thiocarbonic acid is an acid with the chemical formula H2CS3 (or S=C(SH)2). It is an analog of carbonicacid H2CO3 (or O=C(OH)2), in which all oxygen...
carbonate ester (organic carbonate or organocarbonate) is an ester of carbonicacid. This functional group consists of a carbonyl group flanked by two alkoxy...
any acidic impurities from a "crude" liquid, producing a purer sample. Reaction of sodium bicarbonate and an acid produces a salt and carbonicacid, which...
considered an oxoacid of carbon. Orthocarbonic acid is highly unstable. Calculations show that it decomposes spontaneously into carbonicacid and water: H4CO4...
oxoacids (e.g. esters of acetic acid, carbonicacid, sulfuric acid, phosphoric acid, nitric acid, xanthic acid), but also from acids that do not contain oxygen...
-ic acid and -ate for a conjugate acid and its conjugate base, respectively. For example, the conjugate base of acetic acid is acetate. Carbonicacid, which...
of rainwater and groundwater charged with H2CO3 (carbonicacid) and naturally occurring organic acids. The dissolution process produces a distinctive landform...
long-term exposure to carbon dioxide in the air can degrade the material. Carbon dioxide is also the anhydride of carbonicacid: H2CO3 → H2O + CO2 Chromium...
acids produced in the body are nonvolatile except carbonicacid, which is the sole volatile acid. Common nonvolatile acids in humans are lactic acid,...
Propionic acid (/proʊpiˈɒnɪk/, from the Greek words πρῶτος : prōtos, meaning "first", and πίων : píōn, meaning "fat"; also known as propanoic acid) is a naturally...
Beta-keto acids, beta-ketoacids, or 3-oxoacids, such as acetoacetic acid, have the ketone group at the second carbon from the carboxylic acid. They generally...
α-hydroxy-substituted carbonicacid amides. For example, sugar. During the degradation of α-hydroxy-substituted carbonicacid amides, the carbon chain shortens...
panes of hot-houses." (p. 51) "If the quantity of carbonicacid [ CO2 + H2O → H2CO3 (carbonicacid) ] in the air should sink to one-half its present percentage...
of the chemical formation of carbonicacid (H 2CO 3) by the dissolution of dry ice (the solid or frozen form of carbon dioxide – CO 2) in water (H 2O)...
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