Phthalic acid
In a field of chemistry called "Organic Chemistry", which mainly involves the study of carbon-based molecules, phthalic acid, is a dicarboxylic acid, which refers to the two COOH groups present in the molecule. The two carboxylic acids are present on an aromatic ring, here benzene, which is where the systematic name "Benzene-1,2-dicarboxylic acid" is from.
Names | ||
---|---|---|
Preferred IUPAC name
Benzene-1,2-dicarboxylic acid | ||
Other names
1,2-Benzenedioic acid
Phthalic acid Benzene-1,2-dioic acid ortho-Phthalic acid Dicarboxylbenzene Carboxylbenzoic acid 1,2-Phenylenedicarboxylic acid Phenylene-1,2-dicarboxylic acid | ||
Identifiers | ||
3D model (JSmol)
|
||
ChEBI | ||
ChemSpider | ||
ECHA InfoCard | 100.001.703 | |
EC Number |
| |
PubChem CID
|
||
UNII | ||
CompTox Dashboard (EPA)
|
||
| ||
Properties | ||
C 8H 6O 4 | ||
Molar mass | 166.132 g/mol | |
Appearance | white solid | |
Density | 1.593 g/cm3, solid | |
Melting point | 207 °C (405 °F; 480 K)[3] | |
0.6 g / 100 mL [1] | ||
Acidity (pKa) | 2.89, 5.51[2] | |
-83.61·10−6 cm3/mol | ||
Hazards | ||
NFPA 704 |
| |
Related compounds | ||
Related {{{label}}} | {{{value}}} | |
Related compounds | {{{value}}} | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | ||
verify (what is ?) | ||
Infobox references | ||
Phthalic acid is one of three structural isomers of benzenedicarboxylic acid. Which refers to the placement of the two carboxylic acids on the benzene-ring. If there were a gap between them it would be the molecule isophthalic acid, with the systematic name Benzene-1,3-dicarboxylic acid, while if the acid groups were opposing each other, it would be terephthalic acid, with the systematic name Benzene-1,4-dicarboxylic acid.
Synthesis
changeThe molecule "Napthalene", when oxidised by potassium permanganate, or similarly strong oxidizers,[4] gives the molecule Phthalic anhydride, with through hydrolysis with hot water, gives Phthalic acid.[5]
References
change- ↑ "PHTHALIC ACID". hazard.com.
- ↑ Brown, H.C., et al., in Baude, E.A. and Nachod, F.C., Determination of Organic Structures by Physical Methods, Academic Press, New York, 1955.
- ↑ Several melting points are reported, for example: (i) 480. K (NIST website), (ii) 210−211 °C with decomposition (Sigma-Aldrich on-line), (iii) 191 °C in a sealed tube (Ullmann's Encyclopedia of Industrial Chemistry), (iv) 230 °C with conversion to phthalic anhydride and water (J.T.Baker MSDS).
- ↑ "Oxidation of Naphthalene to Phthalic Anhydride". public.websites.umich.edu. Retrieved 2024-06-15.
- ↑ Noller, Carl R. (1965). Chemistry of Organic Compounds (3rd ed.). Philadelphia: W. B. Saunders. p. 602.