CHM 220 Alkanes and Cycloalkanes

Nomenclature and Structure

1. Which of the following is not an IUPAC name for an isomer having the formula C4H9Br?

(A) 1-bromobutane (B) 1-bromo-2-methylpropane (C) 2-bromobutane (D) 1-bromo-3-methylpropane

2. What is the IUPAC name for the compound having the following structure?

(A) 2-methyl-3-chloropentane (B) 2-methyl-3-chlorobutane (C) 1,1-dimethyl-2-chloropropane (D) 2-chloro-3-methylbutane

3. What is the IUPAC name for the compound having the following structure?

(A) 2,2-diethylbutane (B) 2,2,2-triethylethane (C) 3-methyl-3-ethylpentane (D) 3-ethyl-3-methylpentane

4. Which of the following structures have the correct names?

Cl Cl Cl Cl 1. tert-butyl chloride 2. isobutyl chloride 3. sec-butyl chloride 4. n-butyl chloride (A) 1 and 2 (B) 2 and 3 (C) 3 and 4 (D) 1 and 4

5. Which of the following structures have the correct names?

(H3C)3COH OH OH OH 1. tert-butyl alcohol 2. sec-butyl alcohol 3. isobutyl alcohol 4. butane-3-ol (A) 1 and 2 (B) 1 and 3 (C) 2 and 4 (D) 3 and 4

6. What is the correct IUPAC name for the following structure?

H3C CH3

(A) 1,2-dimethylcyclobutane (B) 1,3-dimethylcyclobutane (C) 1,4-dimethylcyclobutane (D)1,3-dimethylbicyclo[1.1.0]butane 7. What is the correct IUPAC name for the following structure?

(A) bicyclo[2.1.0]hexane (B) bicyclo[2.2.1]hexane (C) bicyclo[2.2.0]hexane (D) bicyclo[3.1.0]hexane

8. What is the correct IUPAC name for the following structure?

(A) bicyclo[2.1.1]hexane (B) bicyclo[2.2.1]hexane (C) bicyclo[2.2.0]hexane (D) bicyclo[3.1.0]hexane

9. Which of the following is a secondary alcohol having the molecular structure C4H10?

A (CH3)2CHCH2OH B CH3CH2CHOHCH 3 C OH D (CH3)2CHOH (A) A (B) B (C) C (D) D

10. Which of the following is a primary alcohol having the molecular formula C4H8O? OH OH A B CDOH OH (A) A (B) B (C) C (D) D

11. What is the correct formula for isobutylbromide?

(A) CH3CH2CH2CH(Br)CH3 (B) (CH3)2CHCH2Br

12. How many branched-chain isomers are there of C6H14?

(A) 2 (B) 3 (C) 4 (D) 6

13. How many total isomers are there for dimethylcyclopentane (include cis, trans)?

(A) 3 (B) 5 (C) 7 (D) 9

14. How many isomeric alkanes are there that have the molecular formula C6H14?

(A) 3 (B) 5 (C) 6 (D) 7

15. Which of the following is not a conformer of C5H12? H C CH3 H H 3 H H H C2H5 H H3C CH3 H H H H H H H H3C H H C2H5 CH3 CH3 A BC D 16. Which of the following is a conformer of isobutane?

H H CH3 CH3 H3C CH3 H5C2 H H3C H H H

H H H H H H H H H H CH3 CH3 A BC D

17. Which of the following are gauche forms? H C CH3 CH3 H H 3 H H3C H H H H CH3 H CH3 H H H H H H3C H H CH3 H H H3C H CH3 H H 1 234 5

(A) 1 and 4 (B) 2 and 3 (C) 2 and 4 (D) 3 and 5

18. Which of the following are anti forms? H C CH3 CH3 H H 3 H H3C H H H H CH3 H CH3 H H H H H H3C H H CH3 H H H3C H CH3 H H 1 234 5

(A) 1 and 4 (B) 2 and 3 (C) 2 and 4 (D) 3 and 5

19. Which of the following conformers has the highest energy?

H3C H H3C CH3 H H H CH3

CH3 H CH3 CH3 H H H H H3C H H H H H H H

A B C D

20. Arrange the conformers of 2,3-dimethylbutane in order of increasing stability (least stable to most stable). H C CH3 3 CH3 CH3 H3C CH3 H3C CH3 H3C H CH3 CH3 H3C H H3C H H CH3 H CH H H 3 H CH3 132 4 (A) 1, 2, 4, 3 (B) 4, 1, 3, 2 (C) 2, 4, 3, 1 (D) 4, 2, 1, 3

21. For methylcyclohexane, the axial conformer is less stable than the equatorial because of which of the following gauche interactions?

(A) one methyl-methlyene (B) two methyl-methylene (C) one methyl-methyl (D) two methyl-methyl 22. How many methyl-methylene gauche interactions are there for trans-1,3-dimethylcyclohexane?

(A) 1 (B) 2 (C) 3 (D) 4

23. How many methyl-methylene gauche interactions are there for 1,1-dimethylcyclohexane?

(A) 1 (B) 2 (C) 3 (D) 4

24. Which of the following is the most stable chair form of trans-1-isopropyl-3-methylcyclohexane?

(A) axial isopropyl, equatorial methyl (B) axial isopropyl, axial methyl (C) equatorial isopropyl, axial methyl (D) equatorial isopropyl, equatorial methyl

25. How many cis isomers are there for dimethylcyclobutane?

(A) 1 (B) 2 (C) 3 (D) 4

26. How many trans isomers are there for dimethylcyclopentane?

(A) 1 (B) 2 (C) 3 (D) 4

27. Whcih of the conformations of cyclohexane is most stable?

(A) boat (B) chair (C) twist boat (D) planar

28. What is the order of increasing energy for the different conformers of cyclohexane (most stable first).

1. Boat 2. Chair 3. Twist boat 4. Planar

(A) 1, 3, 4, 2 (B) 4, 3, 1, 2 (C) 2, 3, 1, 4 (D) 2, 1, 4, 3

29. Which of the following are more stable? (most stable from each pair of compounds)

cis- or trans-1,4-dimethylcyclohexane cis- or trans-1,3-dimethylcyclohexane

(A) cis, cis (B) cis, trans (C) trans, cis (D) trans, trans

30. Which of the following are more stable? (most stable from each pair of compounds)

cis- or trans-1,2-dimethylcyclohexane cis- or trans-1,3-dimethylcyclohexane

(A) cis, cis (B) cis, trans (C) trans, cis (D) trans, trans

31. In the most stable conformation of trans-1,4-dimethylcyclohexane, what positions do the methyl groups occupy?

(A) axial, axial (B) equatorial, axial (C) equatorial, equatorial (D) axial, equatorial 32. In the most stable conformation of cis-1-ethyl-2-methylcyclohexane, what positions do the ethyl and methyl groups occupy respectively?

(A) axial, axial (B) equatorial, axial (C) equatorial, equatorial (D) axial, equatorial

33. Which of the following positions is the bridgehead carbon atom? A

D B C

(A) A (B) B (C) C (D) D

34. Whcih isomer of dimethylbicyclo[2.2.2]octane can have cis and trans forms?

(A) 1,2 (B) 2,3 (C) 1,3 (D) 1,4

Properties and Reactions

35. What is the order of increasing boiling point (lowest first) for the following forms of pentane?

123 4

(A) 3, 2, 1, 4 (B) 4, 2, 3, 1 (C) 1, 2, 3, 4 (D) 3, 4, 2, 1

36. Which fuel gives the highest heat upon combustion (per mole)?

(A) natural gas (B) gasoline (C) LPG (liquid propane) (D) all are the same

37. Which of the following contribute most to the strain in cyclopentane?

(A) eclipsed hydrogen atoms (B) bent bonds or angle strain (C) all of the other reasons (D) transannular non-bonded interaction

38. Arrange the following attractive forces in order of increasing energy.

1. covalent bonds 2. hydrogen bonds 3. ionic bonds 4. dispersion forces (Van der Waals)

(A) 4, 2, 1, 3 (B) 2, 4, 1, 3 (C) 3, 2, 4, 1 (D) 2, 1, 3, 4

39. A compound with the molecular formula C6H14 reacted with chlorine in the presence of light to give 5 monochlorinated products. The compound is which of the following?

(A) n-hexane (B) 2,3-dimethylbutane (C) 2-methylpentane (D) 3-methylpentane 40. A hydrocarbon gave only one monochlorinated product when reacted with chlorine and heat. What is the hydrocarbon?

(A) neopentane (B) isobutane (C) 2,3-dimethylbutane (D) 2,2,3,3-tetramethylbutane

41. In which of the following molecules is abstraction of a primary, a secondary and a tertiary hydrogen possible?

(A) neopentane (B) isobutane (C) isopentane (D) cyclopentane

42. Light-catalyzed chlorination of a hydrocarbon is a good synthetic procedure for making which of the following compounds?

1. 2-chlorobutane 2. neopentyl chloride 3. 2-chloro-2-methylpropane 4. cyclohexyl chloride

(A) 2, 4 (B) 1, 2 (C) 3, 4 (D) 2, 3

43. When 2-methylbutane and bromine react with light, what is the order of increasing amounts of products having bromine in the indicated positions (least first)? 1 3 4

2 (A) 1, 2, 3, 4 (B) 4, 2, 3, 1 (C) 1, 4, 3, 2 (D) 2, 3, 4, 1

44. When isobutane and fluorine react, what is the ratio of the products, 1-fluoro-2-methylpropane to 2-fluoro-2- methylpropane?

(A) 9:1 (B) 2:1 (C) 3:1 (D) 1:400

45. What is the most likely ratio of ethyl chloride to methyl chloride when one mole each of methane and ethane are reacted with chlorine and heat?

(A) 1:1 (B) 6:4 (C) 400:1 (D) 4:6