Exercise (Module: What are Things Made of) IJSO Training: What are Things Made of Exercise 1. Identify the hybridization of each of the carbon, oxygen and nitrogen atoms in the following compounds. (a) caffeine (b) Tamiflu O O HN N N H 2N O O N N O 2. Which of the following compounds is a stronger acid? O Give explanation. O H 3C 3. C O H CH 3CH2OH Which of the following compounds is a stronger acid? H2 C O C OH H2C Br F 4. OH Which of the following compounds is a stronger acid? CH 3CH 2CH2CH O C OH F 5. 6. 7. O C Give explanation. CH3CHCH2CH2 O C Give explanation. OH F Predict the H-O-C bond angle of (CH3)3COH. Predict the H-C-H bond angle of formaldehyde. Do the sp2 carbons and the indicated sp3 carbons lie in the same plane? CH3 CH3 Exercise (Module: What are Things Made of) 8. List the following compounds in order of decreasing boiling point, and give explanation. CH3CH2CH3, CH3OCH3, CH3CH2OH, CH3CH2NH2 9. Which of the following compounds have zero dipole moment? H F H F F F H F F H H H 10. Draw all the isomers of C5H12. point. Explain. Identify the one that has the lowest boiling 11. Explain why lead compounds were added to petrol in the past, but it is no longer a current practice. 12. A compound has a molecular formula of C9H10 and has a benzene (phenyl group) in its structure. Draw all the possible isomers of this compound. 13. Which of the following hydrocarbons has the highest boiling point? (a) n-Butane (C4H10) (b) n-Pentane (C5H12) (c) iso-Pentane (C5H12) (d) neo-Pentane (C5H12) 14. Which of the following compounds, when used as refrigerants, has the least adverse effects to the environment (a) Trichlorofluoromethane (CCl3F, CFC-11) (b) Dichlorodifluoromethane (CCl2F2, CFC-12) (c) Chlorodifluoromethane (CHClF2, HCFC-22) (d) Difluoromethane (CH2F2, R-32) 15. Which of the following compounds is hormone that can trigger fruit ripening? (a) Ethane (b) Ethene (c) Ethanol (d) Diethyl ether 16. Which of the following compounds is obtained from the reaction of ethanol (CH3CH2OH) and chloroethane (CH3CH2Cl)? (a) CH3CH=CHCH3 (b) CH3CH2CH2CH2Cl Exercise (Module: What are Things Made of) (c) CH3CH2OCH2CH3 (d) CH3CH2CH2CH2OH 17. What is the name of the following function group? O H (a) (b) (c) (d) aldehyde carboxylic acid ester alcohol 18. Which of the following compounds has the highest boiling point? (a) CH3CH2CH3 (b) CH3OCH3 (c) CH3CH2Cl (d) CH3CH2OH 19. How many compounds that shown below can form cis-trans isomers? CH 3CH CHCH2 CH3 CH 3C CHCH 3 CH 3 (a) (b) (c) (d) 1 2 3 4 CH 3CH CHCH3 CH 3CH 2CH CH 2