Potassium tartrate

Potassium tartrate, dipotassium tartrate or argol has formula K₂C₄H₄O₆. It is the potassium salt of tartaric acid. It is often confused with potassium bitartrate, also known as cream of tartar. As a food additive, it shares the E number E336 with potassium bitartrate.^[1]

Potassium tartrate

Names
IUPAC name Dipotassium 2,3-dihydroxybutanedioate
Other names Dipotassium tartrate; Argol; E336
Identifiers
CAS Number	921-53-9 (L) Y
3D model (JSmol)	Interactive image
ChemSpider	2697916 Y
ECHA InfoCard	100.005.180
PubChem CID	8984
UNII	O9WLL1ZL8S (L) Y
InChI InChI=1S/C4H6O6.2K/c5-1(3(7)8)2(6)4(9)10;;/h1-2,5-6H,(H,7,8)(H,9,10);;/q;2*+1/p-2 Y Key: AVTYONGGKAJVTE-UHFFFAOYSA-L Y InChI=1/C4H6O6.2K/c5-1(3(7)8)2(6)4(9)10;;/h1-2,5-6H,(H,7,8)(H,9,10);;/q;2*+1/p-2 Key: AVTYONGGKAJVTE-NUQVWONBAX
SMILES C(C(C(=O)[O-])O)(C(=O)[O-])O.[K+].[K+]
Properties
Chemical formula	C4H4K2O6
Molar mass	226.268 g/mol
Appearance	colorless, slightly opaque crystals
Density	1.984 g/cm3
Solubility	insoluble in alcohol
Refractive index (nD)	1.550
Structure
Crystal structure	monoclinic
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Potassium bitartrate, also referred to as potassium acid tartrate or cream of tartar,^[2] is the potassium acid salt of l-( + )-tartaric acid. It is obtained as a byproduct of wine manufacture during the fermentation process. Approved by the FDA as a direct food substance, potassium bitartrate is used as an additive, stabilizer, pH control agent, antimicrobial agent, processing aid, or thickener in various food products. Potassium bitartrate has a long history of medical use as a laxative administered as a rectal suppository and is an approved third-class OTC drug in Japan.

Potassium bitartrate was one of active ingredients in Phexxi, a non-hormonal contraceptive agent that was approved by the FDA in May 2020.^[3]