Page 63, Q 1 4 1a) substitution reaction b) addition reaction c) elimination reaction

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1 Unit 2, Lesson 10 and 11: Answers to Homework on the Reactions of Alcohols Page 63, Q 1 4 1a) substitution reaction b) addition reaction c) elimination reaction 2a) oxidation reaction (the terminal carbon is bonded to an additional oxygen atom) b) reduction reaction because the product has more H bonds c) reduction reaction because the product has fewer bonds 3a) the reaction is both addition and reduction because more H bonds have formed b) the reaction is a condensation reaction because two molecules have joined to form one, it is also a dehydration reaction 4a) addition reaction b) oxidation reaction (another bond is formed) Page 64, Q 1a,b,c, 2, 5 1a) addition b) elimination c) substitution 2a) oxidation b) reduction c) reduction d) oxidation e) reduction 5. This reaction is considered a reduction reaction because the number of H bonds is increased. It is an addition reaction because two hydrogen atoms are added across the double bond. Page 67 to 68, Q ethyl-2-heptene + H-H 3-ethyl-3-heptanol + 3-ethyl-2-heptanol H + H 2 H H 3-ethyl-3-heptanol, major product H H 3-ethyl-2-heptanol

2 Page 67 6a) 1-hexene + H 2-bromohexane + 1-bromohexane major product 6b) 2-methyl-2-pentene + H-H 2-methyl-2-pentanol + 2-methyl-3-pentanol major product 7a) H = + 2 H H b) = + H-H c) = H + H H d) ( ) 2 = H + H Page 30, Q 22, 24, 25 22a) methoxy methane b) 2- methoxy propane c) 1- methoxy butane 24a) 1-methoxy propane b) 3-ethoyx-4-methylheptane H H c) tert-butyl-methyl ether

3 Page 30, Q H H f these molecules, the alcohol will be more water-soluble because the H group is more polar ( EN = 1.24) and capable of hydrogen bonding. The bond in ether is less polar ( EN = 0.89) and the group is not capable of hydrogen bonding. Page 45, Q a) ethyl methanoate b) methyl butanoate c) pentyl pentanoate 39a) ethyl methanoate is made from ethanol and methanoic acid b) methyl propanoate is made from methanol and butanoic acid c) pentyl pentanoate is made from pentanol and pentanoic acid 40a) methyl pentanoate, 6 H 12 2 b) heptyl methanoate, 8 H 16 2 H c) butyl ethanoate, 6 H 12 2 d) propyl octanoate, 11 H 22 2 e) ethyl 3,3-dimethyl butanoate, 8 H See molecular formulas, in question 40. heptyl methanoate, 8 H 16 2 and ethyl 3,3-dimethyl butanoate, 8 H 16 2 are isomers methyl pentanoate, 6 H 12 2 and butyl ethanoate, 6 H 12 2 are isomers

4 Page 45, Q Five ester isomers with molecular formula 5H102 are shown. There are many other possibilities, mostly due to branching of alkyl groups. propyl ethanolate ethyl propanoate methyl butanoate butyl methanoate H methyl 2-methyl propanoate H Page 50 51, Q 1, 2, 3a,b,d, 6, 9, 10 1a) methanol (wood alcohol) b) ethanol (grain alcohol) c) 2-propanol or isopropyl alcohol (rubbing alcohol) d) propanone or acetone e) methanal or formaldehyde f) ethanoic acid or acetic acid g) methyl benzene or toluene 2. Answered in question 1. You are expected to know these common names. 3a) pentanal b) 2,3-diethylhexanoic acid d) methyloctanoate

5 Page 50 51, questions 6, 9, butyl ethanoate, 6 H 12 2 hexanoic acid, 6 H 12 2 H 9. The compounds are arranged in order of increasing boiling points. ut of the three compounds above, propanoic acid (on the right) has the highest boiling point. This is because only propanoic acid has an H group which is extremely polar and capable of hydrogen bonding, in addition to the = group. 10. Amines and ketones both have very characteristic odours. Ketones have a sweet, fruity smell while amines smell like rotten fish. Page 73, Q a) substitution b) oxidation c) substitution and oxidation d) dehydration or elimination 10a) H l + Hl + H 2 10b) H + [] H 11a) This reaction can be classified as a dehydration or elimination. H 1-butanol H 2 S 4 H + H 2 1-butene

6 Page 73, Q (continued) 11b) Both steps of the reaction are oxidation reactions. 1-pentanol H [] pentanal [] H pentanoic acid H 11c) This is a substitution reaction. It could also be classified as a reduction reaction. H H H + H H H + H 2 3-methyl-2-butanol 2-bromo-3-methyl butane 11d) This is a substitution reaction. It could also be classified as a oxidation reaction. H 1-bromo-2-methyl propane + NaH H H + H 2-methyl-1-propanol 11e) This is an oxidation reaction. H H + [] 2-butanol butanone 11f) This reaction is a substitution reaction and also a reduction reaction. H l + Hl + H 2 cyclohexanol chlorocyclohexane

7 Page 73, Q Answered in with question The reaction shown below will NT proceed. The alcohol is a tertiary alcohol (the hydroxyl group is bonded to a carbon that is bonded to three other carbons), so it can not be oxidized. H + [] Page 78, Q 14 16a,c,d,f 14a) reduction reaction b) reduction reaction c) reduction reaction d) condensation, dehydration or esterification reaction e) hydrolysis reaction 15a) cyclobutanone cyclobutanol 15b) 2,2,4,4-tetramethyl-3-pentanone 2,2,4,4-tetramethyl-3-pentanol 15c) H H 2-pentanone 2-pentanol 15d) hexanoic acid H H + ethyl hexanoate 15e) butyl methanoate H H H- and H

8 Page 78, Q 16 16a) hexanoic acid H c) methyl propanoate d) 1-propanol and ethanoic acid H H- f) 2-propyl 3-methyl propanoate H H Page 79 80, Q 1, 2, 3, 4, 6, 7 1a) elimination or dehydration b) addition c) oxidation d) redution e) substitution f) substitution g) esterification, dehydration or condensation 2a) 2b) H H 2,3-dibromobutane l H H 2-chlorobutane

9 Page 79 80, Q 2, 3, 4, 6, 7 2c) products are 1-hexene and water: H 2d) products are 3,3-dimethyl-1-butene and H: H 3a) Product is bromobenzene and hydrobromic acid H 3b) product is 1-bromopentane and water: 4a) product is 2-pentanone: 4b) product is propanoic acid: H 4c) product is 2,3-dimethyl butanal: H H H 4d) product is ethane: H 4e) product is 3-pentanol: H 4f) product of first reduction is 1-butene: H = product of second reduction is butane: 4g) product is 2-ethyl-3,4-dimethyloctanol H H H H

10 Page 80 Q 6, 7 6. Markovnikov s Rule states that in addition reactions, the rich get richer, and in elimination reactions, the poor get poorer. What this means is that when you are adding a compound that contains hydrogen across a double bond, the hydrogen atom will be added to the carbon atom that has more hydrogen atoms before the reaction. Similarly, during an elimination reaction, when a hydrogen compound is removed to form a double bond, the hydrogen will be taken from the carbon atom that has fewest hydrogen atoms to start with. Markovnikov s Rule allows us to predict the major product of organic addition and elimination reactions. 7. Reaction a is impossible, because ketones can not be oxidized any further. Reaction b is possible (occurs in two steps). Reaction c is impossible. hlorine can not be added across the bonds in benzene, because these bonds are not truly double bonds, they are 1 ½ bonds long and do not undergo addition reactions. Benzene only does substitution reactions. Reaction d is impossible because the alcohol is a tertiary alcohol which can not be oxidized.