Malic acid
| DL-Malic acid | |
| Names | |
|---|---|
| Preferred IUPAC name 2-Hydroxybutanedioic acid | |
| Other names 
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| Identifiers | |
| 3D model (JSmol) | |
| ChEBI | 
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| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.027.293 | 
| EC Number | 
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| E number | E296 (preservatives) | 
| KEGG | |
| PubChem CID | |
| UNII | |
| CompTox Dashboard (EPA) | |
| 
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| 
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| Properties | |
| C4H6O5 | |
| Molar mass | 134.09 g/mol | 
| Appearance | Colorless | 
| Density | 1.609 g⋅cm−3 | 
| Melting point | 130 °C (266 °F; 403 K) | 
| 558 g/L (at 20 °C) | |
| Acidity (pKa) | pKa1 = 3.40 pKa2 = 5.20 pKa3 = 14.5 | 
| Hazards | |
| GHS labelling: | |
| Flash point | 203 °C | 
| Related compounds | |
| Other anions | Malate | 
| Related carboxylic acids | Succinic acid Tartaric acid Fumaric acid | 
| Related compounds | Butanol Butyraldehyde Crotonaldehyde Sodium malate | 
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
Malic acid is an organic compound with the molecular formula HO2CCH(OH)CH2CO2H. It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms (L- and D-enantiomers), though only the L-isomer exists naturally. The salts and esters of malic acid are known as malates. The malate anion is a metabolic intermediate in the citric acid cycle.