Chapter 11

Draw structural formulas for possible isomers of dichlorinated propane, \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{Cl}_{2}\) Name each compound.

Give structural formulas and systematic names for the three structural isomers of trimethylbenzene, \(\mathrm{C}_{6} \mathrm{H}_{3}\left(\mathrm{CH}_{3}\right)_{3}\)

Give structural formulas and systematic names for possible isomers of dichlorobenzene, \(\mathrm{C}_{6} \mathrm{H}_{4} \mathrm{Cl}_{2}\)

Voodoo lilies depend on carrion beetles for pollination. Carrion beetles are attracted to dead animals, and because dead and putrefying animals give off the horrible-smelling amine cadaverine, the lily likewise releases cadaverine (and the closely related compound putrescine, page 501 ). A biological catalyst, an enzyme, converts the naturally occurring amino acid lysine to cadaverine. (EQUATION CANNOT COPY) What group of atoms must be replaced in lysine to make cadaverine? (Lysine is essential to human nutrition but is not synthesized in the human body.)

Benzoic acid occurs in many berries. When humans eat berries, benzoic acid is converted to hippuric acid in the body by reaction with the amino acid glycine, \(\mathrm{H}_{2} \mathrm{NCH}_{2} \mathrm{CO}_{2} \mathrm{H} .\) Draw the structure of hippuric acid, recognizing that it is an amide formed by reaction of the carboxylic acid group of benzoic acid and the amino group of glycine. Why is hippuric acid referred to as an acid?

Consider the reaction of cis-2-butene with \(\mathrm{H}_{2}\) (in the presence of a catalyst). (a) Draw the structure and give the name of the reaction product. Is this reaction product chiral? (b) Draw an isomer of the reaction product.

Kevlar is a polyamide made from \(p\) -phenylenediamine and terephthalic acid. (It is used to make bullet-proof vests, among other things.) Draw the repeating unit of the Kevlar polymer. (EQUATION CANNOT COPY)

A well-known company selling outdoor clothing has recently introduced jackets made of recycled polyethylene terephthalate (PET), the principal material in many softdrink bottles. Another company makes PET fibers by treating recycled bottles with methanol to give the diester dimethylterephthalate and ethylene glycol and then repolymerizing these compounds to give new PET. Write a chemical equation to show how the reaction of PET with methanol can give dimethylterephthalate and ethylene glycol.

Draw the structure of glyceryl trilaurate. When this triester is saponified, what are the products?

Write a chemical equation describing the reaction between glycerol and stearic acid to give glyceryl tristearate.

You have a liquid that is either cyclohexene or benzene. When the liquid is exposed to dark red bromine vapor, the vapor is immediately decolorized. What is the identity of the liquid? Write an equation for the chemical reaction that has occurred.

Hydrolysis of an unknown ester of butyric acid, \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CO}_{2} \mathrm{R}\) produces an alcohol A and butanoic acid. Oxidation of this alcohol forms an acid \(\mathrm{B}\) that is a structural isomer of butanoic acid. Give the names and structures for alcohol \(\mathrm{A}\) and acid \(\mathrm{B}\).

You are asked to identify an unknown colorless, liquid carbonyl compound. Analysis has determined that the formula for this unknown is \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O} .\) Only two compounds match this formula. (a) Draw structures for the two possible compounds. (b) To decide which of the two structures is correct, you react the compound with an oxidizing agent, and isolate from that reaction a compound that is found to give an acidic solution in water. Use this result to identify the structure of the unknown. (c) Name the acid formed by oxidation of the unknown.

An unknown colorless liquid has the formula \(\mathrm{C}_{3} \mathrm{H}_{8} \mathrm{O} .\) Draw the structures for the three compounds that have this formula.

Addition of water to alkene \(\mathbf{X}\) gives an alcohol \(\mathbf{Y}\). Oxidation of \(\mathbf{Y}\) produces 3,3 -dimethyl-2-pentanone. Identify \(\mathbf{X}\) and \(\mathbf{Y}\), and write equations for the two reactions.

An unknown ester has the formula \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2} .\) Hydrolysis gives methanol as one product. Identify the ester and write an equation for the hydrolysis reaction.

Identify the reaction products and write an equation for the following reactions of \(\mathrm{CH}_{2}=\mathrm{CHCH}_{2} \mathrm{OH}\) (a) \(\mathrm{H}_{2}\) (hydrogenation, in the presence of a catalyst) (b) oxidation (excess oxidizing agent) (c) addition polymerization (d) ester formation, using acetic acid

What important properties do the following characteristics impart to an polymer? (a) cross-linking in polyethylene (b) the OH groups in polyvinyl alcohol (c) hydrogen bonding in a polyamide-like nylon

Describe a simple chemical test to tell the difference between \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}=\mathrm{CH}_{2}\) and its isomer cyclopentane.

Describe a simple chemical test to tell the difference between 2 -propanol and its isomer methyl ethyl ether.

Maleic acid is prepared by the catalytic oxidation of benzene. It is a dicarboxylic acid; that is, it has two carboxylic acid groups. (a) Combustion of 0.125 g of the acid gives \(0.190 \mathrm{g}\) of \(\mathrm{CO}_{2}\) and \(0.0388 \mathrm{g}\) of \(\mathrm{H}_{2} \mathrm{O} .\) What is the empirical formula of the acid? (b) A 0.261 -g sample of the acid requires 34.60 mL of \(0.130 \mathrm{M} \mathrm{NaOH}\) for complete titration (so that the \(\mathrm{H}^{+}\) ions from both carboxylic acid groups are used). What is the molecular formula of the acid? (c) Draw a Lewis structure for the acid. (d) Describe the hybridization used by the C atoms. (e) What are the bond angles around each C atom?

Addition reactions of hydrocarbons are described on the General ChemistryNow CD-ROM or website Screen 11.4. In the Simulation you learn that the product of an addition reaction of an alkene is controlled by Markovnikov's rule. (a) Draw the structure of the product obtained by adding HBr to propene, and give its name. (b) Draw the structure and give the name of the compound that results from adding \(\mathrm{H}_{2} \mathrm{O}\) to 2 -methyl- 1 butene. (c) If you add \(\mathrm{H}_{2} \mathrm{O}\) to 2 -methyl-2-butene, is the product the same or different than the product from the reaction in part (b)?