Fumaric Acid
Fumaric Acid questions and answers
Learn more about Fumaric Acid at Diet & Health.net.
Q: How do we know that maleic acid and fumaric acid are isomers and not the same molecule ?
bonus : 2 /how do we know that molecules cannot rotate around a C=C double bond ?
Thank you for your replying
A: Salaam,
► We don't..
Q: any one know where I can purchase fumaric acid in vitamin form?
I seem to recall it being a additive in some product but I can't remember what. I understand it is good for psorisis.
A: please visit your medical store & ask them
Q: why does maleic acid and fumaric acid have different pka?
how can the difference in their isomeric structures be accounted for the different pKa's?
A: educated guess:the pseudo six member ring that maleic acid forms should help stabliize the ion. when it loses its proton, the negative charge develops on that oxygen. it can move down and push the double bond of its neighbour oxygen up, giving it the negative charge. conveniently enough (which isn't the case for fumarate), the other proton that hasn't left yet is right beside the newly developed negative charge, which that negative oxygen can take to become a hydroxyl, giving the negative charge to the oxygen on the opposite end of the molecule. this "resonance" stabliizes the charge, thus the ion is stable and the proton is more acidic.
Q: Anyone know when Fumaric Acid will be available in the USA for Psoriasis?
My Germand friends tell me it works miracles on their stubborn Psoriasis.
A: If you have bad psoriasis try Enbrel, it works wonders.
Q: what are the possible products of the bromination of fumaric acid.?
I would like to know all possible enantiomers or/and meso compounds that can be formed as well as their properties. I would also like to know the stereospecificity of the reaction
A: ask at http://chemions.grou.ps
Q: How can you convert maleic acid into fumaric acid?
...by using HCl and water?
A: From the Wikipedia ...
"In the classroom, maleic acid is transformed into Fumaric acid through the process of heating the maleic acid to a high temperature in a 12mol HCl solution. The heated molecule loses a water molecule and becomes an acid anhydride while in the heated solution. Once the heat is removed, the acid anhydride takes back the water molecule, but reforms as fumaric acid, the more stable isomer of butenedioic acid. This isomer is more stable because the carboxyl groups are no longer on the same side of the molecule, but are now on opposite sides, causing the molecule to become non-polar. That is why it comes out of the polar HCl solution, as a polar solvent will not dissolve a non-polar solute."
Q: Fumaric Acid vs Maleic Acid which one is more stable?
Fumaric Acid vs Maleic Acid which one is more stable
if possible please explain
Thanks in advance
A: Fumaric acid has a trans double bond. This is of lower energy than the cis double bond and thus is more stable.
Q: what type of stereochemistry is represented by maleic and fumaric acid?
thanks
A: Hi
they are geometrical isomers. maleic acid is the cis isomer and fumaric acid is the trans isomer of butandioic acid.
geometrical isomerism is a form of sterochemistry with double bonds so the molecules vary by the spacial arrangement on the double bonds
I hope that helps
Q: why does fumaric acid product precipitate from the reaction mixture?
A: Because of the acidicity of everything. It has compounds that have reactions when combined with other chemicals.
Q: Fumaric and Maleic Acid?
I know that fumaric acid is more stable, but I don't know why. Can anyone explain?
A: Fumaric acid is the trans isomer of Maleic acid. The CO2H are on the opposite side thus steric repulsion is lesser than in the case of Maleic acid where the CO2H are on the same side
Q: Maleic acid to Fumaric Acid?
I need the balanced/unbalanced equation for the conversion of maleic acid to fumaric acid using HCl. Also a little help determining the theoretical yield would be great! Thanks!
A: treat the compound with the acid then the carbocation formed will be tetrahedral and free rotation will yied the requisite trans geometry .the elimination of the acid can give the product.
better method will be to use iodine and sunlight.
Q: How do you change Maleic acid to Fumaric acid? DETAILS?
include repulsion, steric interaction, rotation and delocaization
A: Maleic acid could be easily transformed into fumaric acid using bromine-cataylzed conversion. Maleate and fumarate are cis- and trans- isomers of C4H4O4. In a bromine-catalyzed conversion, light causes the bromine, a diatomic species Br2, to form a radical Br. The radical Br attacks the double bond in the acids and forms a radical butene molecule. Since the double bond has become a single bond, the C-C bond may go through bond rotations, either changing it from cis- or trans- forms. The radical Br then forms a stabled Br2 molecule, hence the double bond reappears where there is a pair of delocalized electrons around the two carbons. Mind you that all of this reactions occurs in equilibrium.
Q: I need help in finding the equivalents of chemicals eg. we use Maleic Anydride, equivalent is Fumaric Acid?
use Maleic Anydride the substitute or equivalent is Fumaric Acid
A: They are almost the same, Maleic anhydride is the dehydrated version of fumaric acid. A unit of water removed form fumaric acid results in a ring closure.
They can be the same if Maleic anhydride was used in an aqueous environment with an acid or base catalyst, it will add water and form fumaric acid.
Heating of fumaric acid will force the dehydration to maleic anhydride.
Q: how come maleic acid is more acidic than fumaric acid?
A: Since in maleic acid both carboxyl groups are at the same side of the molecule, while in fumaric acid they are in opposite sizes. In maleic acid, after the first H+ dissociate, the negative ion is much stable due to both oxygen atoms may have strong inetraction with the left H atom. In another word, the first H+ is much easier to dissociate. With the same reason, the second H+ would be more difficult to dissociate in maleic acid than in fumaric acid. Therefore, since the first H+ in maleic acid is much easier to dissociate, maleic acid is more acidic than fumaric acid.
Q: Which is more stable?Maleic acid or fumaric acid?
A: Fumaric acid being the trans isomer will have the least stearic hindrance as the carboxylic acid groups will be on the different sides of the double bonds-hence causing the least electronic repulsion. Hence will be more stable as compared to Maleic acid