2. Sketch the following molecules: 3-cyclohexenone 4-ethyl 2,2,5-trimethyl 3-hexanone ethyl butyrate pentanoic acid 2-chloro 4-methyl 2,5-heptadienal 3,4-dichloro 4-ethyl octanal p-chloro phenol 3-bromo 2-chloro 4-methyl hexane 3-cyclopropyl 1,2-cyclopentanediol methyl phenyl ether 3,5-dimethyl 2-heptene-4,5-diol 3. Give two different uses for ethanol. 4. Name two categories of organic compounds (alkanes, aldehydes…) that have very strong characteristic odours. .