Question

Weeks 48 5: Hydrogenation of methyl oleate to give methyl stearate . Understand the reaction stoichiometry for this lab, including balanced equation. Is Pd/C consumed in the reaction? How is H2 gas generated, and is it stoichiometric or catalytic in this reaction? Be able to identify limiting reagent, calculate theoretical and percent yield. . Why is the starting material an oil, while the product is solid (if pure)? Understand the intermolecular forces involved, and how these are different for the product vs. the starting material (functional groups and molecular shape). What does it mean if your product is an oil, and not the expected product? Understand the reaction mechanism for the unsaturation tests (Br2), be able to interpret the data from this kind of experiment.

Answer 1

-Hydrogenation of methyl Oleate occurs as Hz C (CLT, CH = CH ACHLtch once the Pelle (catalyst) the test, cy-cth terbt, c o-cth Methyl stearate Hy gas can be generated from reaction of Zn with strong acid or by electrolysis of water. the is used stochiometrically. dimiting reagent is methye oleate Ro n Pellc is catalyst and is not Consumed in readron. Starting material, methyl cleate, is an unsaturated fatty acid. Because of double bond present, it is an oil. Methyl Stearate, product, is a saturated fatty acid. It is has only single bonds and so is solid in nature Methyl oleate has a kink in its structure while methyl stevate has zig-zag structure which allows proper fitting of molecules This raises the melting point. of product is oil, it means reaction did not occur. Cadets or it is not complete On adding Bry, if the color is discharged, it means reactant is present of color color is not discharged, it means reaction is complete