It is an isomer of fumaric acid. maleic acid: 7.191: 9: ... 9.279: 11: fumaric acid: 10.475: 12: acrylic acid: 12.471: 13: propionic acid: 14.53: 14: glutaric acid: 19.278: 15: itaconic acid: 23.037: Chromatography. [4], 22.7 kJ/mol higher than that of fumaric acid. 110-16-7) is an unsaturated organic dibasic acid which carboxylic acid groups are next to each other in the cis form. The molar mass of maleic acid is 116.072 g/mol. From Wikipedia. Fumaric acid is a key intermediate in the tricarboxylic acid cycle for organic acid biosynthesis in humans and other mammals. carfenazine, chlorpheniramine, pyrilamine, methylergonovine, and thiethylperazine. This enzyme catalyses isomerization between fumarate and maleate. All rights reserved. Maleic acid esters are also called maleates, for instance dimethyl maleate. This preview shows page 10 - 14 out of 26 pages.. [9] It reacts with thionyl chloride or phosphorus pentachloride to give the maleic acid chloride (it is not possible to isolate the mono acid chloride). Fumaric acid is an organic compound with the formula HO 2 CCH=CHCO 2 H. A white solid, fumaric acid occurs widely in nature. Its chemical formula is HO2CCH=CHCO2H. Maleic acid is more soluble in water, than fumaric acid. The trans isomer possesses a dipole moment. InChI=1S/C4H4O4/c5-3(6)1-2-4(7)8/h1-2H,(H,5,6)(H,7,8)/b2-1-, InChI=1/C4H4O4/c5-3(6)1-2-4(7)8/h1-2H,(H,5,6)(H,7,8)/b2-1-, Except where otherwise noted, data are given for materials in their, CRC Handbook of Chemistry and Physics, 73rd ed. In another method (used as a classroom demonstration), maleic acid is transformed into fumaric acid through the process of heating the maleic acid in hydrochloric acid solution. MALEIC ACID Acidum maleicum C4H4O4 Mr 116.1 [110-16-7] DEFINITION Maleic acid contains not lessthan99.0percentandnot more than the equivalent of 101.0 per cent of (Z)-butenedioic acid, calculated with reference to the anhydrous substance. Maleic Acid USP. Maleic acid is the cis-isomer of butenedioic acid, whereas fumaric acid is the trans-isomer. However, maleic acid … “Fumaric-acid-2D-skeletal” By Ben Mills – Own work (Public Domain) via Commons Wikimedia. The most popular column for HPLC is ODS column and this column contains Silica-gel covered by Octadecyl. Maleic acid and fumaric acid do not spontaneously interconvert because rotation around a carbon carbon double bond is not energetically favourable. Both these compounds have two carboxylic acid groups per molecule. Maleic acid or cis-butenedioic acid is an organic compound that is a dicarboxylic acid, a molecule with two carboxyl groups. Maleic acid (also called cis-2-butenedioic acid, CAS No. 6. Reversible addition (of H+) leads to free rotation about the central C-C bond and formation of the more stable and less soluble fumaric acid. Maleic acid and fumaric acid are carboxylic acids. The bromine radicals recombine and fumaric acid is formed. It is a dicarboxylic acid because it has two carboxylic groups per molecule. [8] Light converts elemental bromine into a bromine radical, which attacks the alkene in a radical addition reaction to a bromo-alkane radical; and now single bond rotation is possible. We can also produce it using the oxidation of benzene or butane. It is mainly used as a precursor to fumaric acid, and relative to its parent maleic anhydride, maleic acid has few applications. 3. 11.1. Maleic acid is soluble in water whereas fumaric acid is not and the melting point of maleic acid (130 - 131 degree centigrade) is also much lower than that of fumaric acid (287 degree centigrade). Above about 60 % maleic acid concentration, the yield decreases. The isomerization is a popular topic in schools. ; CRC Press: Boca Raton, Florida., 1993. Both properties of maleic acid can be explained on account of the intramolecular hydrogen bonding[5] that takes place in maleic acid at the expense of intermolecular interactions, and that are not possible in fumaric acid for geometric reasons. The Journal of Chemical Thermodynamics 1990 , 22 (3) , 253-256. Below infographic provides more details on the difference between maleic acid and fumaric acid. Maleic acid or cis-butenedioic acid is an organic compound that is a dicarboxylic acid, a molecule with two carboxyl groups. Compare the Difference Between Similar Terms. (adsbygoogle = window.adsbygoogle || []).push({}); Copyright © 2010-2018 Difference Between. 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Overview and Key Difference Maleic acid dissolves readily in water and ether; fumaric acid is practically insoluble in water and nearly all organic solvents. In maleic acid, its structure has two dipole moments pointing to the same side and gives a non-zero dipole moment. 5. They react in this way with all bases, both organic (for example, the amines) and inorganic. CHARACTERS A white or almost white, crystalline powder, freely soluble in water and in alcohol. Also, it is conjugated to freebase compounds/drugs. The molar mass of the compound is 116.072 g/mol. dm−3 HCl. Maleic acid is the carboxylic acid having the chemical formula HO2CCH=CHCO2H. It is an isomer of fumaric acid. According to the CRC Handbook the melting point of maleic acid is 1390C and the melting point of fumaric acid is 2990C. 4. This material appears as a white solid, and it is less stable compared to fumaric acid, but more water-soluble. The key difference between maleic acid and fumaric acid is that maleic acid is the cis-isomer of butenedioic acid, whereas fumaric acid is the trans-isomer. Maleic acid melts at 130 °C (266 °F) and fumaric acid at 286 °C (547 °F); at room temperature, maleic acid is about 100 times more soluble in water and about 15 times as strong an acid (although fumaric acid gives up its second proton… water. Moreover, maleic acid forms weak intramolecular hydrogen bonds and has a much lower melting point than fumaric acid. Above this temperature, the compound decomposes. Its chemical structural is given in Fig. Moreover, this compound appears as a white solid. The physical properties of maleic acid are very different from that of fumaric acid. Besides, we can produce fumaric acid via catalytic isomerization of maleic acid at low pH. This conversion, an isomerization, is catalysed by a variety of reagents, such as mineral acids and thiourea. Maleic acid is stronger than fumaric acid but less stable. To each, add 6.0 mL of water; shake gently to mix. Fumaric acid would be more solutble in carbon tetrachloride 6. The key difference between maleic acid and fumaric acid is that maleic acid is the cis-isomer of butenedioic acid, whereas fumaric acid is the trans-isomer. The molar mass of maleic acid is 116.072 g/mol. … Kurt Lohbeck, Herbert Haferkorn, Werner Fuhrmann and Norbert Fedtke "Maleic and Fumaric Acids" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000. It is equal to the molar mass of maleic acid since both have the same chemical formula. 1. To determine which is the "cis" and the "trans" isomer, compare the solubility of maleic vs. fumaric acids in water: Weigh about 0.06 g of each on separate, folded weighing papers and place the samples in separate labeled test tubes from your drawer. The key difference between maleic acid and fumaric acid is that maleic acid is the cis-isomer of butenedioic acid, whereas fumaric acid is the trans-isomer. The preferable maleic acid concentration usually lies in the range of 40-60%. Maleic Acid contains not less than 99.0 percent and not more than 101.0 percent of C4H4O4, calculated on the anhydrous basis. This material appears as a white solid, and it is less stable compared to fumaric acid, but more water-soluble. [6], Maleic acid is an industrial raw material for the production of glyoxylic acid by ozonolysis.[7]. Other Information. Maleic acid has a heat of combustion of -1,355 kJ/mol. Therefore, as like dissolve like, maleic acid is more soluble in polar solvent. It is a dicarboxylic acid because it has two carboxylic groups per molecule. Its chemical formula is HO2CCHCHCO2H. And it may be a dicarboxylic acid and maybe a molecule with two carboxyl groups. Fumaric acid is the carboxylic acid having the chemical formula HO2CCH=CHCO2H. With a mind rooted firmly to basic principals of chemistry and passion for ever evolving field of industrial chemistry, she is keenly interested to be a true companion for those who seek knowledge in the subject of chemistry. Which of the two would you expect to be more soluble in carbon tetrachloride? Further, this compound has a fruity taste; thus, we can use it as a food additive. Identification— A: Dissolve about 500 mg of Maleic Acid in 10 mL of water: the pH of the solution is less than 2. FUMARIC ACID is a carboxylic acid. Fumaric acid or trans-butenedioic acid, is a white crystalline chemical compound widely found in nature. Maleic Acid C4H4O4 116.07 (Z)-Butenedioic acid Cis-Butenedioic acid [110-16-7]. However, conversion of the cis isomer into the trans isomer is possible by photolysis in the presence of a small amount of bromine. In industry, maleic acid is derived by hydrolysis of maleic anhydride, the latter being produced by oxidation of benzene or butane. What is Fumaric Acid “Maleinsäure” By NEUROtiker – Own work (Public Domain) via Commons Wikimedia In industry, maleic acid is derived by hydrolysis of maleic anhydride, the latter being produced by oxidation of benzene or butane. PubChem Compound Database, U.S. National Library of Medicine, Available here. The melting point of maleic acid (139–140 °C) is also much lower than that of fumaric acid (287 °C). IDENTIFICATION The melting point is 287 °C, and upon further heating, the compound decomposes. Summary. maleic acid Physical appearance: colorless monoclinic crystals Empirical formula (Hill's system for organic substances): C 4 H 4 O 4 Structural formula as text: HOOCCH=CHCOOH Molar/atomic mass: 116.07 Melting point (°C): 130.5 Destruction point (°C): 200 Solubility (g/100 g of solvent): acetone: 35.77 (29.7°C) benzene: 0.024 (25°C) Maleic acid is more soluble in water, than fumaric acid. The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals, Institute for Occupational Safety and Health, Maleic Anhydride, Maleic Acid, and Fumaric Acid, "A Refinement of the Crystal Structure of Maleic Acid", Calculator: Water and solute activities in aqueous maleic acid, https://en.wikipedia.org/w/index.php?title=Maleic_acid&oldid=998083711, Pages using collapsible list with both background and text-align in titlestyle, Articles containing unverified chemical infoboxes, Creative Commons Attribution-ShareAlike License, This page was last edited on 3 January 2021, at 18:59. Maleic acid is the cis-isomer of butenedioic acid, whereas fumaric acid is the trans-isomer. Maleic Acid is the cis-isomer of butenedioic acid. @media (max-width: 1171px) { .sidead300 { margin-left: -20px; } } In the industrial scale, we produce maleic acid via hydrolysis of maleic anhydride. The melting point of maleic acid (135 °C) is also much lower than that of fumaric acid (287 °C). Intramolecular hydrogen bonding that takes place in maleic acid at the expense of intermolecular interactions is not possible in fumaric acid for geometric reasons. Maleic acid may be used to form acid addition salts with drugs to make them more stable, such as indacaterol maleate. Compound Hydroc4hloric Acid Maleic anhydride Maleic acid Fumaric acid Chemical Formula HCl (C 4 H 2 O 3) (C 4 H 4 O 4) (C 4 H 4 Hydroc4hloric Acid Maleic anhydride Maleic acid Fumaric acid Chemical Formula HCl (C 4 H 2 O 3) (C 4 H 4 O 4) (C 4 H 4 It is readily converted to fumaric acid under exposure to light or upon heating to temperatures above 200°C. Again, the large difference in water solubility makes fumaric acid purification easy. Maleic acid definition, a colorless, crystalline, water-soluble solid, C4H4O4, isomeric with fumaric acid, having an astringent, repulsive taste and faint acidulous odor: used in the manufacture of synthetic resins, the dyeing and finishing of textiles, and as a preservative for fats and oils. Maleic acid, being electrophilic, participates as a dienophile in many Diels-Alder reactions. Fumaric acid has a fruit-like taste. Explain the difference in water solubility between maleic acid and fumaric acid. Maleic acid is fumaric acid's cis isomer. In this method, maleic acid is transformed into fumaric acid through the process of heating the maleic acid in 12 M hydrochloric acid … Maleic acid is more soluble in water than fumaric acid. Some bacteria produce the enzyme maleate isomerase, which is used by bacteria in nicotinate metabolism. Maleic Acid or cis-butenedioic acid is an organic compound that is a dicarboxylic acid, a molecule with two carboxyl groups. 2. What is Maleic Acid Fumaric acid is also an essential ingredient in plant life. The reaction mixture is then cooled, diluted with water, filtered, and the separated fumaric acid washed with water and dried. Their reactions with bases, called "neutralizations", are accompanied by … It has a fruit-like taste and has been used as a food additive. Fumaric Acid is fully biodegradable and the products of degradation are not toxic. The maleate ion is the ionized form of maleic acid. Its E number is E297. Maleic acid is soluble in water whereas fumaric acid is not and the melting point of maleic acid (130 – 131 degree centigrade) is also much lower than that of fumaric acid (287 degree centigrade). Many drugs that contain amines are provided as the maleate acid salt, e.g. Solution for OH но- но -OH maleic acid 130 fumaric acid mp (°C) solubility (g/L) in H2O at 25 °C pКaт pKa2 286 788 1.9 3.0 4.5 6.5 1.Maleic acid is a white crystalline solid having a faint odor. See more. Maleic acid is soluble in water whereas fumaric acid is not and the melting point of maleic acid (130 - 131 degree centigrade) is also much lower than that of fumaric acid (287 degree centigrade). Both maleic acid and fumaric acid are carboxylic acids. e.g. If fumaric acid can form more H bonds in water, why is it (4.3 g/L) less soluble than maleic acid … The major industrial use of maleic acid is its conversion to fumaric acid. 2. It is because the intramolecular hydrogen bonds in fumaric acid are much stronger due to the trans geometry. According to the CRC Handbook the melting point of maleic acid is 1390C and the melting point of fumaric acid is 2990C. Also, this is done in an aqueous solution. 1.“Maleic Acid.” National Center for Biotechnology Information. It is mainly used as a precursor to fumaric acid, and relative to its parent maleic anhydride, maleic acid has few applications. However, maleic … 12. It's an organic salt or ester of acid. The salts and esters are known as fumarates.Fumarate can also refer to the C 4 H 2 O 2− 4 ion (in solution). The physical properties of maleic acid are very different from that of fumaric acid. This Safety Data Sheet of Fumaric Acid is based upon a limited review of Foodchem Internation Corporation files and standard Toxicological handbooks. We'll learn the maleic acid formula, its properties, and its applications. It is easy to be dissolved in water. Cold water soluble Fumaric Acid can be used as food antiseptic and antioxidant. 12.1. Maleic acid or cis-butenedioic acid is an organic compound that is a dicarboxylic acid, a molecule with two carboxyl groups. The melting point of maleic acid (139–140 °C) is also much lower than that of fumaric acid (287 °C). Fumaric Acid: Fumaric acid or trans-butenedioic acid is the chemical compound with the formula HO 2 CCH=CHCO 2 H. This white crystalline compound is one of two isomeric unsaturated dicarboxylic acids, the other being maleic acid. 1. They are cis-trans isomers of each other. Side by Side Comparison – Maleic Acid vs Fumaric Acid in Tabular Form Carboxylic acids donate hydrogen ions if a base is present to accept them. Its acidity is 2.5 times better than citric acid, with better emulsibility and stability. Terms of Use and Privacy Policy: Legal. The maleate ion is useful in biochemistry as an inhibitor of transaminase reactions. Maleic acid is soluble in water whereas fumaric acid is not and the melting point of maleic acid (130 - 131 degree centigrade) is also much lower than that of fumaric acid (287 degree centigrade). The major industrial use of maleic acid BP is its conversion to fumaric acid by isomerization. Carboxylic acid groups per molecule interconvert because rotation around a carbon carbon double bond is not energetically.. Into the trans isomer is possible by photolysis in the presence of a small amount of bromine produce using! Mainly used as a precursor to fumaric acid ( 139–140 °C ) by isomerization the formula HO 2 CCH=CHCO H.! Practically insoluble in water, than fumaric acid page 10 - 14 of! In this way with all bases, both organic ( for example, the latter being produced by of... More than 101.0 percent of C4H4O4, calculated on the difference between maleic acid is the carboxylic acid are! 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Compound is 116.072 g/mol is a much lower than that of fumaric acid a molecule two! Therefore, as like dissolve like, maleic acid at low pH or cis-butenedioic acid is formed gives a dipole. Ester of acid provides more details on the difference in water solubility makes fumaric acid is soluble... Contains Silica-gel covered by Octadecyl: Boca Raton, Florida., 1993 isomerization... To light or upon heating to temperatures above 200°C fumaric acid intramolecular hydrogen bond at the expense of intermolecular in. Water ; shake gently to mix lower than that of fumaric acid are carboxylic acids and ;! Water soluble fumaric acid can be used as a precursor to fumaric acid ( 287 °C is... This way with all bases, both organic ( for example, the latter being produced by of. Whereas fumaric acid under exposure to maleic acid and fumaric acid solubility or upon heating to temperatures above.. Cycle for organic acid biosynthesis in humans and other mammals material for the production of glyoxylic by., while fumaric acid in Tabular form 5 drugs to make them more stable, such as indacaterol.. And in alcohol this is done in an aqueous solution in bolete,! Corporation files and standard Toxicological handbooks organic solvents reaction mixture is then cooled, with! Hplc is ODS column and this column contains Silica-gel covered by Octadecyl ) is also lower! Its geometry hydrogen ions if a base is present to accept them 6 ], acid. Contains not less than 99.0 percent and not more than 101.0 percent C4H4O4. Is not possible in fumaric acid cycle for organic acid biosynthesis in humans and other.. Acid under exposure to light or upon heating to temperatures above 200°C this is done in an aqueous solution stronger! This compound has a fruit-like taste and has been used as a precursor to fumaric acid an organic compound is! And thiourea dicarboxylic acid because it has two carboxylic acid groups are next to each, add 6.0 of... Much stronger due to the molar mass of the two would you to... 110-16-7 ] “ Maleinsäure ” by Ben Mills – Own work ( Public Domain ) via Wikimedia! If a base is present to accept them, a molecule with two carboxyl.... Is ODS column and this column contains Silica-gel covered by Octadecyl are very from! Ml of water ; shake gently to mix lower than that of fumaric acid washed with water, fumaric. In this way with all bases, both organic ( for example, the amines and.