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Bashar Almaraziq

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Bashar Almaraziq

Organic Chemistry Test Bank – Chapter 7

In every slide, you will find a question with 2 – 5 choices.

The answers of the questions will be in the last slide, so don’t forget to write your answers (To check them 💪).

*** You can use the periodic table anytime 😊.

1. Which one of the following is a secondary alcohol?

A. CH3CH2OH.

B. CH3OH.

C. CH3CH(OH)CH3.

D. (CH3)C3OH.

E. None of the above.

2. The IUPAC name for: (CH3)2CHCH(OH)CH2C(CH3)3.

A. 2,5,5-trimethyl-3-hexanol.

B. 1,1,4,4-pentamethylbutanol.

C. 1,1-dimethylisopentanol.

D. 2,5-dimethyl-4-hexanol.

E. None of the above.

3. Which is NOT a physical property of alcohols or phenols?

A. Phenols are generally only slightly soluble in water.

B. The solubilities of normal primary alcohols in water decrease with increasing molecular weight.

C. The hydroxyl group of an alcohol is nonpolar.

D. Due to hydrogen bonding, boiling points of alcohols are much higher than those of corresponding alkanes.

E. Boiling points of normal primary alcohols increase with increasing molecular weight.

4. How many alcohols are structural isomers with the formula: C5H11OH?

A. 5.

B. 6.

C. 7.

D. 8.

E. 9.

5. Dehydration of an alcohol leads to the formation of an __________.

A. Alkene.

B. Alkane.

C. Alkyne.

D. Alkyl halide.

E. Aldehyde.

6. Ethanol can be oxidized stepwise. What is the first stable intermediate product when ethanol is oxidized with a mild oxidation agent?

A. CH3COOH.

B. CO2.

C. CH3CHO.

D. CH3CH2OH.

E. CH3OCH3.

7. Which of the following alcohols forms a ketone when oxidized?

A. 1-propanol.

B. Methanol.

C. 2-methyl-2-propanol.

D. 2-propanol.

E. All of the above.

8. The name of the structure below is (Try name it by yourself without a clue):

9. The following alcohol is:

A. Primary.

B. Secondary.

C. Tertiary.

D. Quaternary.

E. It is not alcohol.

10. The following alkyl bromide is:

A. Primary.

B. Secondary.

C. Tertiary.

D. Quaternary.

E. It is not alcohol.

11. Write the complete name of the following, including stereochemistry if it is specifically shown (Try name it by yourself without a clue):

12. The correct arrangement of the following compounds (In terms of rate of dehydration) is:

A. A > B.

B. B > A.

C. A = B.

D. Can’t be determined.

A B

13. The correct arrangement of the following compounds (In terms of rate of SN2 substitution by HBr) is:

A. A > B > C.

B. A > C > B.

C. B > A > C.

D. B > C > A.

E. C > B > A.

A B C

14. The best reagent to use in this reaction to make it right is:

A. HCl / H2O.

B. HCN / H2O.

C. H2SO4 / H2O.

D. HCOOH / H2O.

E. None of the above.

15. The following reaction is:

A. An addition reaction.

B. An elimination reaction.

C. A substitutional reaction.

D. An oxidation reaction.

E. Can’t be determined.

16. The name of the structure below is (Try name it by yourself without a clue):

17. PCC could be used to prepare:

A. A secondary alcohol.

B. An aldehyde.

C. A ketone

D. A carboxylic acid.

E. Two of the above.

18. Write the complete name of the following, including stereochemistry if it is specifically shown (Try name it by yourself without a clue):

19. The name of the structure below is (Try name it by yourself without a clue):

20. Which one of the following compound is obtained by the oxidation of primary alcohol?

A. Alkanal.

B. Alkanone.

C. Ether.

D. Amine.

E. No reaction will happen.

21. Which one of the following compound is obtained by the oxidation of secondary alcohols by [O]?

A. Alkanal.

B. Alkanone.

C. Ether.

D. Amine.

E. No reaction will happen.

22. Which of the following alcohols would be most soluble in water?

A. Propanol.

B. Butanol.

C. Pentanol.

D. Hexanol.

23. What is the reagent to convert isopropyl alcohol to isopropyl bromide?

A. PCC.

B. HBr.

C. Br2.

D. CH3MgBr.

24. The major reason that phenol is a better Bronsted acid than cyclohexanol is ____________.

A. It is a better proton donor.

B. The cyclohexyl group is an electron donating group by induction, which destabilizes the anion formed in the

reaction.

C. Phenol is able to stabilize the anion formed in the reaction by resonance.

D. The phenyl group is an electron withdrawing group by induction, which stabilizes the anion formed in the

reaction.

25. When phenol is treated with excess of bromine and water, it gives which of the following product?

A. m-bromophenol.

B. o-and p-bromophenol.

C. 2,4-dibromophenol.

D. 2,4,6-tribromophenol.

26. How many hydroxyl groups are present in tetrols?

A. One.

B. Two.

C. Three.

D. Four.

27. Glycerin is a dihydric alcohol:

A. True.

B. False.

28. Hydroquinone is the same as parahydroxyphenol:

A. True.

B. False.

29. What is the general formula for dihydric alcohol?

A. (CH2)n(OH)2 where n = 2,3…etc.

B. (CH2)n(OH)2 where n = 1,2,4… etc.

C. CnH2n+1OH where n = 1, 2 …etc.

D. (CH2)n(OH)3 where n = 3, 4, 5 …etc.

30. Which of the following compounds is not a product of the following reaction?

A. A.

B. B.

C. C.

D. D.

A B

C D

31. Which of the following statements about alcohols is incorrect?

A. Tertiary alcohols have lower boiling points than primary alcohols with an equivalent molecular weight.

B. Alcohols undergo nucleophilic substitution.

C. Tertiary alcohols undergo dehydration more readily than primary alcohols.

D. Tertiary alcohols are metabolized in the body to ketones.

32. Which of the following alcohols would be oxidized to propan-2-one?

A. Ethanol.

B. Propan-2-ol.

C. 2-methylpropan-2-ol.

D. Butan-1-ol.

33. Why do alcohols undergo nucleophilic substitution reactions with hydrogen halides?

A. The acid protonates the OH group and changes the leaving group from a hydroxide ion to a water molecule.

B. The acid protonates the OH group and changes the leaving group from a hydroxide ion to a hydroxyl radical.

C. Substitutions always need to be carried out at low pH values.

D. The acid protonates the OH group and changes the leaving group from a hydroxide radical to a water

molecule.

34. Which of the following is a true statement?

A. Only primary alcohols react with hydrogen halides, and they react by an SN2 pathway.

B. All types of alcohols react with hydrogen halides by way of an SN1 reaction.

C. Only tertiary alcohols react with hydrogen halides, and they react by an SN1 pathway.

D. All types of alcohols react with hydrogen halides by way of an SN2 reaction.

E. All types of alcohols react with hydrogen halides, and the mechanism depends on the structure of the

alcohol.

35. What is the major product obtained from the acid-catalyzed dehydration of 1-methylcyclohexanol?

A. Methylcyclohexane.

B. Methylenecyclohexane.

C. 1-methylcyclohexene.

D. 2-methylcyclohexene.

E. 3-methylcyclohexene.

36. What product is formed when 1,2-dimethylcyclohexanol undergoes acid-catalyzed dehydration?

A. 1,2-dimethylcyclohexene.

B. 1,3-dimethylcyclohexene.

C. 2,2-dimethylcyclohexene.

D. 2,3-dimethylcyclohexene.

E. 1,6-dimethylcyclohexene.

37. Why do primary alcohols undergo SN2 reactions with hydrogen halides?

A. They have poor leaving groups.

B. They are very reactive.

C. They form unstable carbocations.

D. They have little steric hindrance.

E. They undergo elimination reactions.

38. Which of the following is a true statement?

A. Primary, secondary, and tertiary alcohols undergo SN1 reactions with HBr.

B. Primary, secondary, and tertiary alcohols undergo SN2 reactions with HBr.

C. Primary alcohols undergo SN1 reactions with HBr; secondary and tertiary alcohols undergo SN2 reactions

with HBr.

D. Primary alcohols undergo SN2 reactions with HBr; secondary and tertiary alcohols undergo SN1 reactions

with HBr.

39. The mechanism by which alcohols undergo nucleophilic substitution reactions with hydrogen halides is dependent on which of the following?

A. The structure of the alcohol.

B. The reaction temperature.

C. The stability of the carbocation that would be formed.

D. The concentration of the alkyl halide.

E. A and C.

40. Which of the following is not true about the acid-catalyzed dehydration of a secondary alcohol?

A. It is an E1 reaction.

B. It is an irreversible reaction.

C. The carbocation loses a proton from the carbon adjacent to the positively charged carbon that is bonded to

the fewest hydrogens.

D. The first step is protonation of the oxygen.

E. A carbocation is formed as an intermediate.

41. Which of the following alcohols will not be oxidized to a ketone?

A. 2-butanol.

B. 1-butanol.

C. 2-methyl-2-butanol.

D. 2-pentanol.

E. B and C.

42. Which of the following alcohols would undergo acid-catalyzed dehydration most rapidly?

A. 1-methylcyclohexanol.

B. 2-methylcyclohexanol.

C. 3-methyl-2-hexanol.

D. 3-methylcyclohexanol.

E. 4-methyl-2-hexanol.

43. CrO3 could be used to prepare:

A. A secondary alcohol.

B. An aldehyde.

C. A ketone

D. A carboxylic acid.

E. Two of the above.

44. We put small amount of KMnO4 in two test tubes. The results shown below. Predict the contents of the test tubes:

A. A: Alkane. B: Alcohol, and alkene before.

B. A: Alkane. B: Alkene, and alcohol before.

C. A: Alcohol, and alkyne before. B: Haloalkane.

D. A: Alcohol, and alkene before. B: Ketone.

E. A: Alkene, and alcohol before. B: Alkane.

A B

45. A thiol is generally more acidic than an alcohol.

A. True.

B. False.

The key answers

Question No. Answers Question No. Answers Question No. Answers Question No. Answers Question No. Answers

1. C 10. A 19. 3-phenyl-1-hexanol 28. A 37. C

2. A 11. trans-4-vinylcyclohexanol 20. A 29. B 38. D

3. C 12. A 21. B 30. A 39. E

4. D 13. D 22. A 31. D 40. B

5. A 14. E 23. B 32. B 41. E

6. C 15. C 24. C 33. A 42. A

7. D 16. 2,3-heptanediol 25. D 34. E 43. E

8.6-bromo-4-ethyl-5,5-dimethyl-2-

hexanol17. E 26. D 35. C 44. C

9. B 18.cis-4,4-dimethyl-

1,2-cyclopentanediol

27. B 36. A 45. A