Sodium hydrogen carbonate

from Wikipedia, the free encyclopedia
Structural formula
Structure of sodium hydrogen carbonate
Surname Sodium hydrogen carbonate
other names
  • Sodium hydrogen carbonate
  • Baking soda
  • Emperor soda
  • bicarbonate of soda
  • Sodium bicarbonate
  • Sodium bicarbonate
  • Baking soda
  • Bullrich Salt
  • E  500 (ii)
Molecular formula NaHCO 3
Brief description

colorless, odorless, crystalline solid

External identifiers / databases
CAS number 144-55-8
EC number 205-633-8
ECHA InfoCard 100.005.122
PubChem 516892
ChemSpider 8609
DrugBank DB01390
Wikidata Q179731
Molar mass 84.01 g mol −1
Physical state



2.22 g cm −3 (20 ° C)

Melting point

Decomposition from 270 ° C

pK s value

moderate in water (96 g l −1 at 20 ° C)

safety instructions
GHS labeling of hazardous substances
no GHS pictograms
H and P phrases H: no H-phrases
P: no P-phrases
Toxicological data

4220 mg kg −1 ( LD 50ratoral )

Thermodynamic properties
ΔH f 0

−950.8 kJ / mol

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Sodium hydrogen carbonate (common name : soda ) has the empirical formula NaHCO 3 , is a sodium salt of carbonic acid and is one of the hydrogen carbonates . The compound should not be confused with sodium carbonate (soda, empirical formula Na 2 CO 3 ). Occasionally, the outdated and chemically incorrect trivial names bicarbonate of soda and sodium bicarbonate (also NaBi for short ) are used for sodium hydrogen carbonate . In trade, the connection is also under the names baking soda , baking soda , baking soda , baking soda offered and brand names.


The word Natron has existed in German since the beginning of modern times (in the forms anatron , natrum and natron ) and originated (like Spanish, French and English natron and " sodium ") from Arabic naṭrūn (or anatrūn ; cf. the Lower Egyptian "Natrontal") "Wadi an-Natrūn" , from which a mixture of sodium carbonate and sodium hydrogen carbonate was used to draw water from mummies) from Greek nítron (νίτρον) (Herodotus; Attic lítron (λίτρον) ), which can be traced back to ancient Egyptian ntr . The Greek nítron (soda, soda, saltpeter) was also used in Latin (sal) nitrum and German salniter (from which nitrogen , nitrate , etc. can then be derived).

Almost a century ago, in the dictionary of the Egyptian language by Adolf Erman and Hermann Grapow , Greek nítron (νίτρον) and Hebrew neter / nether were linked with the ancient Egyptian word nṯr.j , which was pronounced / natsₑra- / in the 2nd millennium BC . Since the Natron word was found in many unrelated but neighboring languages ​​during this period, this etymology must be considered probable.

Ancient Egyptian nṯr.j does not mean “divine” in relation to baking soda and does not refer to baking soda as a divine substance, as is often read. All objects and substances used to prepare a corpse for burial and mummification are generally called nṯr.j , for example mummy bandages and mummification devices , i.e. “ items belonging to the burial”.


Sodium hydrogen carbonate occurs as a natural mineral Nahcolith in the United States among others. It usually occurs finely divided in oil shale and can then only be obtained as a by-product of oil production. Particularly rich Nahcolith horizons are mined in the state of Colorado ; the annual production in 2007 was 93,440 tons. There are also localities in Europe.


Reaction of saturated sodium carbonate solution with carbon dioxide with cooling:

This is an equilibrium reaction, but it is strongly shifted to the right due to the relatively poor solubility of sodium hydrogen carbonate. The filtered sodium hydrogen carbonate must be carefully dried so that it does not decompose again (in reverse of the formation reaction).

In this way it was presented for the first time by the pharmacist Valentin Rose the Younger in Berlin in 1801.

In the Solvay process precipitating sodium hydrogen carbonate as an intermediate product (mainly due to the co-precipitated impurities ammonium chloride ) are not normally used.


Sodium hydrogen carbonate is a colorless, crystalline solid that decomposes above a temperature of 50 ° C with elimination of water and carbon dioxide to form sodium carbonate.

In contrast to sodium carbonate , it dissolves in water with only a weakly alkaline reaction.

Sodium hydrogen carbonate has a monoclinic crystal structure with the space group P 2 1 / c (space group no. 14) and the lattice parameters a = 3.51  Å , b = 9.71 Å, c = 8.05 Å and β = 111 ° 51 ′ . The compound forms mixed crystals with sodium carbonate. Template: room group / 14


Sodium hydrogen carbonate is mainly used to make baking soda and effervescent powder. The global production volume is in the 100,000 ton range.

The connection has a wide range of uses in general:

  • In food technology
  • In sports nutrition
    • When used and dosed appropriately in healthy, trained and not malnourished people, a positive effect on endurance can be either proven or likely.
  • In the medicine
    • for brushing teeth (soda or baking soda is contained in many toothpastes , especially in countries like the USA), but not because of an often - but incorrectly - assumed abrasive effect
    • in professional tooth cleaning (PZR) in prophylaxis (dentistry)
    • as a heartburn remedy because of the neutralization effect with the formation of non-toxic reaction products (CO 2 and water); is now considered out of date (see antacid , proton pump inhibitor ). NaHCO 3 is still contained in many products for heartburn and acid-related stomach problems. For example, Bullrich Salt consists of 100% sodium hydrogen carbonate.
    • as an antidote for poisoning by barbiturates , salicylates and tricyclic antidepressants
    • as part of a drinking solution (together with potassium chloride , sodium chloride and macrogol ) for colon cleansing as preparation for a colonoscopy (colonoscopy).
    • as a buffer substance to compensate for the base deficit during hemodialysis (acidosis correction). In the so-called bicarbonate dialysis , sodium hydrogen carbonate is probably the most important component of the dialysate. In contrast to acetate or lactate, NaHCO 3 does not have to be metabolized in order to be effective. Because of its benefits for the cardiovascular system, it is the most frequently used buffer substance in hemodialysis worldwide. In addition, this procedure is less likely to cause drops in blood pressure, nausea, and cramps.
    • for the treatment of metabolic acidosis and hyperkalemia
  • In aviation technology
    • for heat absorption and for creating a fire-retardant atmosphere in flight recorders
  • In environmental technology
    • As a sorbent for acidic exhaust gas components (SO x , HCl) in flue gas cleaning systems (Bicar process)
  • History of the dehydration of corpses ( mummification )
  • In agriculture
    • as a remedy against fungal diseases such as powdery mildew and gray rot , known under the name Steinhauer's powdery mildew fright
    • as a pH value buffer in dairy cattle feeding
    • as a cheese ripening agent (pH blunting, in sour milk cheese dairy) and to delay the coagulation of milk
  • As a component of fire extinguishing powders (release of CO 2 when heated)
  • For stretching synthetic drugs like amphetamines and for making crack from cocaine
  • In the household
    • as a component of mild detergents
    • as a cleaning agent to remove encrusted food residues. The effect is partly due to the saponification of fatty food residues
    • A pinch of baking soda in the cooking water softens peas, lentils and beans faster and removes the bloating effect of various types of cabbage.
    • As an addition to the finished cheese fondue , it makes it easier to digest and airy.
    • It neutralizes odors: bad breath, drainage pipes, musty shoes, refrigerator, litter box, cages for small animals.
    • As a remedy against ants and cockroaches: If you sprinkle baking soda in the holes of the ant burrow and on the ant paths, the ants pick up the baking soda and carry it into their burrow. Baking soda changes the pH in the ants' body, which leads to death.
    • Excess acid in food is neutralized or weakened by baking soda. This is important when preparing jams from sour fruits such as sea ​​buckthorn or rhubarb , as this gives them a milder taste and less sugar has to be used. Vinegar or lemon juice that is excessively added to a meal can also be neutralized by baking soda.
  • In the aquarium hobby and in pool water
    • to increase the buffer capacity to prevent an acid fall
    • to regulate the KH value , e.g. B. in saltwater aquariums , or to regulate the alkalinity in swimming pools (so-called Alka-Plus products consist of sodium hydrogen carbonate)
  • In toy rockets , it is used together with vinegar or citric acid as fuel (through the formation of the gas carbon dioxide)
  • In the laboratory to neutralize spilled acids, mostly as a 5% solution.
  • As a non-abrasive blasting agent in blasting technology , see soda blasting .

Biological importance

It reacts with acids in a foaming manner, forming carbon dioxide and water.

Sodium hydrogen carbonate and hydrochloric acid react to form sodium chloride , carbon dioxide and water.

The ability to neutralize acids with HCO 3 - is vital for the body.

  • In the stomach due to the active there must enzymes an acidic environment rule, this is done by production of hydrogen chloride (HCl) to give together with water of gastric juice (about 0.5 percent hydrochloric acid) forms, their pH (fasted) to can drop to 1–1.5. The epithelial cells of the stomach wall, which would perish immediately at such a low pH value, protect themselves by releasing mucus mixed with HCO 3 - . If H + ions in the hydrochloric acid penetrate the mucous layer, they are neutralized to form CO 2 and water. The CO 2 mostly escapes through the esophagus.
  • In turn, an alkaline environment is required in the small intestine , as other enzymes take over the cleavage of the nutrients. The change of the pH value takes place in the duodenum ( the duodenum ) by feeding the secretion of the pancreas , which among other things also - as the output in the stomach mucus - HCO 3 - contains.
  • Hydrogen carbonate HCO 3 - is the most important blood buffer for regulating the acid-base balance in humans.

Web links

Commons : Sodium Hydrogen Carbonate  - Collection of pictures, videos and audio files
Wiktionary: Sodium hydrogen carbonate  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. Entry on E 500 (ii): Sodium hydrogenate carbonate in the European database for food additives, accessed on June 27, 2020.
  2. Entry on SODIUM BICARBONATE in the CosIng database of the EU Commission, accessed on February 25, 2020.
  3. a b c Data sheet sodium hydrogen carbonate (PDF) from Merck , accessed on January 19, 2011.
  4. a b c d e f g Entry on sodium hydrogen carbonate in the GESTIS substance database of the IFA , accessed on December 19, 2019(JavaScript required) .
  5. ^ A b Robert N. Goldberg, Nand Kishore, Rebecca M. Lennen: Thermodynamic quantities for the ionization reactions of buffers in water . (PDF) In: J. Phys. Chem. Ref. Data . 31, No. 2, 2002, p. 264. Retrieved July 16, 2014.
  6. David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-19.
  7. Renate Gerner: Instruments and substances used in mummification. In: Renate Gerner, Rosemarie Drenkhahn (ed.): Mummy and Computer. A multidisciplinary research project in Hanover. Special exhibition of the Kestner Museum Hanover from September 26, 1991 to January 19, 1992. Kestner Museum, Hanover 1991, ISBN 3-924029-17-2 , p. 28 f.
  8. ^ Franz Dornseiff: The Greek words in German. Walter de Gruyter & Co, Berlin 1950, p. 44.
  9. ^ Friedrich Kluge , Alfred Götze : Etymological dictionary of the German language . 20th edition, ed. by Walther Mitzka , De Gruyter, Berlin / New York 1967; Reprint (“21st unchanged edition”) ibid 1975, ISBN 3-11-005709-3 , p. 504.
  10. Presentation of the US Geological Survey on Nahcolith Reserves in Colorado (PDF 12 MB).
  11. a b c d e A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 , p. 1182.
  12. ^ RL Sass, RF Scheuerman: The crystal structure of sodium bicarbonate. In: Acta Crystallographica. 15, 1962, pp. 77-81, doi : 10.1107 / S0365110X62000158 .
  13. Michael Stierwald: On the effectiveness and usefulness of selected ergogenic substances in sport . Diploma theses agency, 2010, ISBN 3-8366-4942-X , p. 43 ( limited preview in Google Book search).
  14. Sports nutrition and sports nutrition: a current inventory. Retrieved October 26, 2011 .
  15. ^ Wilfried Umbach: Cosmetics and hygiene: from head to toe . John Wiley & Sons, 2012, ISBN 3-527-66350-9 ( limited preview in Google Book Search).
  16. Toothpaste abrasiveness index - RDA values. In: Retrieved February 3, 2016 .
  17. W. Forth, D. Henschler, W. Rummel: General and special pharmacology and toxicology . 9th edition. URBAN & FISCHER, Munich 2005, ISBN 3-437-42521-8 .
  18. Ernst Mutschler et al .: Mutschler - drug effects textbook of pharmacology and toxicology . 9th edition. Scientific Verlagsgesellschaft, Stuttgart 2008, ISBN 978-3-8047-1952-1 .
  19. Antidote monograph for sodium hydrogen carbonate (PDF; 60 kB).
  20. Package insert for relevant products such as Moviprep, Prepacol, Endofalk, Klean Prep, CitraFleet
  21. ^ Rainer Nowack, Rainer Birck, Thomas Weinreich: Dialysis and nephrology for specialists . Springer-Verlag, 2009, ISBN 978-3-540-72323-3 , p. 110 .
  22. hemodialysis. In: DocMedicus Verlag GmbH & Co. KG, accessed on February 3, 2016 .
  23. Wolfgang Hartig: Nutritional and infusion therapy: standards for clinics, intensive care units and ... Georg Thieme Verlag, 2004, ISBN 3-13-130738-2 , p. 326 ( limited preview in Google Book search).
  24. Franz-Josef Kretz, Karin Becke: Anesthesia and intensive care medicine in children - Franz-Josef Kretz, Karin Becke . Georg Thieme Verlag, 2007, ISBN 3-13-157212-4 , p. 151 ( limited preview in Google Book search).
  25. US patent. Retrieved April 18, 2014 .
  26. Indirect weed control in winter wheat ( Memento of the original from May 18, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed May 17, 2014. @1@ 2Template: Webachiv / IABot /
  27. Effects of feeding errors and metabolic disorders on hoof health :: , accessed on May 17, 2014.
  28. Entry on sodium hydrogen carbonate. In: Römpp Online . Georg Thieme Verlag, accessed on May 17, 2014.
  29. Thomas Geschwinde: Drugs: Market forms and modes of action . Springer DE, 2013, ISBN 3-642-30163-0 , p. 530 ( limited preview in Google Book search).
  30. ^ Günter Wagner: detergents - chemistry, environment, sustainability . John Wiley & Sons, 2011, ISBN 3-527-64366-4 , pp. 100 ( limited preview in Google Book search).
  31. a b c Christa Pöppelmann: SOS. How do you do that ?: What you really have to be able to do! Compact Verlag, 2010, ISBN 3-8174-7922-0 ( limited preview in Google book search).
  32. Softkill with Soda , article by Christoph Drösser on Zeit Online , April 30, 2009, accessed on June 16, 2013.
  33. Georg Schwedt: Even more experiments with supermarket products: The periodic table as a guide . John Wiley & Sons, 2012, ISBN 3-527-66139-5 ( limited preview in Google Book Search).
  34. ↑ Construction instructions on the subject of aquariums and aquaristics: Increase PH value & KH with baking soda ( Memento of the original from May 17, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed May 17, 2014 @1@ 2Template: Webachiv / IABot /
  35. The Effervescent Powder Rocket , accessed on October 4, 2015.
  36. Bikarbonatbatterie, SE Miederer, Fortschr Med.1994, June 10; 112 (16): 235-8, PubMed