2-mercaptopropionic acid
Structural formula | |||||||||||||||||||
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( R ) shape (left) and ( S ) shape (right) | |||||||||||||||||||
General | |||||||||||||||||||
Surname | 2-mercaptopropionic acid | ||||||||||||||||||
other names |
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Molecular formula | C 3 H 6 O 2 S | ||||||||||||||||||
Brief description |
colorless liquid with a rancid odor |
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External identifiers / databases | |||||||||||||||||||
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properties | |||||||||||||||||||
Molar mass | 106.15 g mol −1 | ||||||||||||||||||
Physical state |
liquid |
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density |
1.196 g cm −3 (25 ° C) |
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Melting point |
10-14 ° C |
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boiling point |
203-208 ° C |
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Vapor pressure |
1.7 hPa (20 ° C) |
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solubility |
soluble in water |
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Refractive index |
1.4809 (20 ° C) |
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safety instructions | |||||||||||||||||||
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Toxicological data | |||||||||||||||||||
Thermodynamic properties | |||||||||||||||||||
ΔH f 0 |
−468.4 kJ / mol |
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C |
2-mercaptopropionic acid , also called thiolactic acid, is an organic chemical compound that is required for the synthesis of herbicides and is also used in depilatory creams . The ammonium salt of thiolactic acid, ammonium thiolactate, is used similarly to ammonium thioglycolate for the permanent wave in the hairdressing salon.
Isomerism
2-mercaptopropionic acid is chiral , so there are two enantiomers , ( R ) -thiolactic acid and ( S ) -thiolactic acid. Whenever “thiolactic acid” is spoken of without any additional designation, a 1: 1 mixture ( racemate ) of ( R ) -thiolactic acid and ( S ) -thiolactic acid is always meant. This mixture is called precisely ( RS ) -thiolactic acid [synonym: ( RS ) -2-mercaptopropionic acid].
Individual evidence
- ↑ a b c d e f g h Entry on 2-mercaptopropionic acid in the GESTIS substance database of the IFA , accessed on January 8, 2020(JavaScript required) .
- ↑ a b Data sheet 2-mercaptopropionic acid (PDF) from Merck , accessed on April 29, 2014.
- ↑ 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. 5-24.
- ↑ External identifiers of or database links to (RS) ammonium thiolactate : CAS number: 13419-67-5, EC number: 236-526-4, ECHA -InfoCard: 100.033.192 , PubChem : 114517 , ChemSpider : 102571 , Wikidata : Q2823310 .