Question

Postlab Questions 1. How fumaric acid and maleic acid are structurally different compounds and how that affects their physical and chemical properties. 2. Include drawings of the structures of maleic and fumaric acid to illustrate your point, 3. Calcuate the reaction yield. Show all calculations. 4 Although maleic and fumaric acid are two different isomers, cis and trans isomers of succinic acid (HOOC-CH2-CH2-COOH) do not exist. Explain and use drawings of all molecules to illustrate your argument. 5 Which of the isomers do you expect to be more soluble in water? Explain why one isomer is more soluble than the other.

Answer 1

HO OH maleic acid fumaric acid

succinic acid

Since maleic acid is the cis isomer and fumaric acid is a trans isomer. Maleic acid exists in anhydride form and the melting point will be lesser compared to fumaric acid and the former is less stable compared to the latter as in fumaric acid there will be strong intermolecular hydrogen bonding.

Chemical properties: Maleic acid dehydrates and forms an anhydride and by hydration, it can be converted to malic acid.

Since succinic acid is not having any unsaturated carbon which is the primary source for cis-trans isomerism. That is why it is lagging of cis-trans isomerism.

Maleic acid will be less soluble compared to fumaric acid because the former will be having intramolecular hydrogen bonding while as the latter will be having intermolecular hydrogen bonding.