Sodium carbonate

Athanor · official

CNa₂O₃ · 105.988 g/mol

IUPAC name: disodium;carbonate

Also called soda ash, washing soda, E500

Inorganic

Open in Athanor

Drawn from its SMILES with RDKit

WarningCauses serious eye irritation

Names and identifiers

IUPAC name: disodium;carbonate
Synonyms: soda ash, washing soda, E500
+ 38 more
Soda Ash, Disodium carbonate, Carbonic acid disodium salt, Sodium carbonate, anhydrous, Calcined soda, Solvay soda, Sodium carbonate anhydrous, Washing soda, Bisodium carbonate, Carbonic acid, disodium salt, Carbonic acid sodium salt, Carbonic acid sodium salt (1:2), Soda, calcined, Soda-ash, Snowlite I, Light Ash, Natrum carbonicum, V Soda, Na2CO3, Anhydrous sodium carbonate, Natriumkarbonat, Soda Ash Light 4P, Suprapur 6395, Crystol carbonate, Dynamar L 13890, Natrium Carbonicum Siccatum, Natrium Carbonicum Calcinatum, Sodium carbonate (anhydrous), Sodium salt of carbonic acid, Sodium carbonate (2:1), V 20N, Sodium Carbonate, Anhydrous ASTM D458, Dried sodium carbonate, INS NO.500(I), Caswell No. 752, INS-500(I), Sodium Carbonate, Anhydrous GE Materials D4D5, 45P3261C7T
Molecular formula: CNa₂O₃
Empirical formula: CNa₂O₃
Molecular weight: 105.988 g/mol
Exact mass: 105.96428
CAS number: 497-19-8
PubChem CID: 10340
Canonical SMILES: C(=O)([O-])[O-].[Na+].[Na+]
Isomeric SMILES: C(=O)([O-])[O-].[Na+].[Na+]
InChI: InChI=1S/CH2O3.2Na/c2-1(3)4;;/h(H2,2,3,4);;/q;2*+1/p-2
InChIKey: CDBYLPFSWZWCQE-UHFFFAOYSA-L
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: White ... small crystals or monoclinic powder[3]
4 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Dry Powder; Other Solid; Large Crystals; CBI; Dry Powder; Large Crystals; Liquid; Wet Solid; Other Solid; Liquid; Dry Powder; Liquid; Liquid; Other Solid [1] EPA Chemical Data Reporting (CDR)
– WHITE HYGROSCOPIC POWDER. [2] ILO-WHO International Chemical Safety Cards (ICSCs)
– Grayish-white powder or lumps containing up to 99% sodium carbonate [3] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 1230
–shown White ... small crystals or monoclinic powder [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V5: 3993
Melting point: 851 °C[2]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
851 °Cshown 851 °C [2] ILO-WHO International Chemical Safety Cards (ICSCs)
851 °C 851 °C [4] PAC Chemical Database, U.S. Department of Energy
Boiling point: Reported, but no value passed the checks.
The value and why
Decomposes on heating by CO2 loss (could not be read; source [3])
Density: 2.509 @ 0°C[4]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
– 2.5 g/cm³ [2] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown 2.509 @ 0°C [4] PAC Chemical Database, U.S. Department of Energy
1 more value was reported but failed the checks (unreadable or out of range), so it is not shown.
Solubility in water: Solubility in water, g/100ml at 20 °C: 30 (freely soluble)[2]
5 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– Solubility in water at 0, 10, 20 and 30 °C is 6, 8.5, 17 and 28 wt %, respectively. [3] Hazardous Substances Data Bank (HSDB)cites Eggeman T; Sodium Carbonate. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2017). New York, NY: John Wiley & Sons. Online Posting Date: 14 Jan 2011
– Soluble in water [3] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 1230
– Sparingly soluble in ethanol; insoluble in acetone [3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V5: 3993
– For more Solubility (Complete) data for Sodium carbonate (6 total), please visit the HSDB record page. [3] Hazardous Substances Data Bank (HSDB)
–shown Solubility in water, g/100ml at 20 °C: 30 (freely soluble) [2] ILO-WHO International Chemical Safety Cards (ICSCs)
Refractive index: Index of refraction: 1.489[3]

Value	As written	Source
–	Dry Powder; Other Solid; Large Crystals; CBI; Dry Powder; Large Crystals; Liquid; Wet Solid; Other Solid; Liquid; Dry Powder; Liquid; Liquid; Other Solid	[1] EPA Chemical Data Reporting (CDR)
–	WHITE HYGROSCOPIC POWDER.	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
–	Grayish-white powder or lumps containing up to 99% sodium carbonate	[3] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 1230
–shown	White ... small crystals or monoclinic powder	[3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V5: 3993

Value	As written	Source
851 °Cshown	851 °C	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
851 °C	851 °C	[4] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	2.5 g/cm³	[2] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown	2.509 @ 0°C	[4] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	Solubility in water at 0, 10, 20 and 30 °C is 6, 8.5, 17 and 28 wt %, respectively.	[3] Hazardous Substances Data Bank (HSDB)cites Eggeman T; Sodium Carbonate. Kirk-Othmer Encyclopedia of Chemical Technology. (1999-2017). New York, NY: John Wiley & Sons. Online Posting Date: 14 Jan 2011
–	Soluble in water	[3] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 1230
–	Sparingly soluble in ethanol; insoluble in acetone	[3] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 12th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2012., p. V5: 3993
–	For more Solubility (Complete) data for Sodium carbonate (6 total), please visit the HSDB record page.	[3] Hazardous Substances Data Bank (HSDB)
–shown	Solubility in water, g/100ml at 20 °C: 30 (freely soluble)	[2] ILO-WHO International Chemical Safety Cards (ICSCs)

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 6
Rings: 0
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 0
H-bond acceptors: 3
Rotatable bonds: 0
TPSA (Å²): 63.2
Formal charge: 0
Complexity: 18 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: D3h of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C11.33%
Na43.38%
O45.29%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: -8.44 Crippen (Wildman and Crippen 1999)
log S (water solubility): 4.82 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 5.36 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 105.99
log P ≤ 5 (Crippen): -8.44
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 3

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Warning

Harmonized EU classification (CLP Annex VI). Source [5].

Harmful or irritant

H319Causes serious eye irritation

Precautionary statements: P264+P265, P280, P305+P351+P338, P337+P317

View all classifications (6)

[5] Regulation (EC) No 1272/2008 of the European Parliament and of the Council · WarningH319
[6] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 0.2% (19 of 8784) of reports.
[6] European Chemicals Agency (ECHA) · 8,784 reports · WarningH319
[6] European Chemicals Agency (ECHA) · 54 reportsThis chemical does not meet GHS hazard criteria for 100% (54 of 54) of all reports.
[6] European Chemicals Agency (ECHA) · 21 reports · WarningH319
[3] Hazardous Substances Data Bank (HSDB) · WarningH319

First aid

Fresh air, rest.[2]
Rinse skin with plenty of water or shower.[2]
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.[2]
Rinse mouth. Give one or two glasses of water to drink. Refer for medical attention .[2]

Storage

Dry. Well closed. Separated from incompatible materials. See Chemical Dangers.[2]
Keep container tightly closed in a dry and well-ventilated place. Hygroscopic. Keep in a dry place. Storage class (TRGS 510): Non Combustible Solids.[3]
Calcined soda ash is hygroscopic, gradually taking up moisture and carbon dioxide during transportation and storage. This converts the surface of sodium carbonate to the bicarbonate and leads to a weight increase of up to 17%. Soda ash is therefore best stored in closed, dry areas.[3]
It migrates to food from packaging materials.[3]

Incompatibilities

The anhydrous reaction of sodium carbonate & phosphorus pentoxide, initiated by local heating, can generate relatively high temp.[3]
When sodium carbonate was applied to red hot aluminum, an explosion occurred.[3]
Stratified concentrated sulfuric acid in a reaction tank was suddenly contacted by alkali wash. The violent ensuing reaction caused a geyser of material, propelled by carbon dioxide and steam, to shoot from the manhole of the tank.[3]
For more Hazardous Reactivities and Incompatibilities (Complete) data for Sodium carbonate (8 total), please visit the HSDB record page.[3]

Safety data sheets on the supplier’s page: Aladdin Scientific, BOC Sciences, eMolecules.

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[2]ILO-WHO International Chemical Safety Cards (ICSCs) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[3]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[4]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[5]Regulation (EC) No 1272/2008 of the European Parliament and of the Council · EU reuse policy, CC BY 4.0 · via PubChem · retrieved 2026-10-14
[6]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[7]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.