3.19: Quiz 3C
- Page ID
- 19275
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- Clearly indicate true (T) or false (F) for the following statements (2 pts each):
| _____ | A chair conformer with substituents in the equatorial position is less stable. |
| _____ | The stronger the acid, the more stable the conjugate base. |
| _____ | Cyclopropane has more ring strain than cyclohexane, which is why molecules containing cyclopropane are often used for rocket fuel or explosives. |
- Give the best answer for the following multiple choice questions: (2 pts each)
Indicate which of the following molecules has a conjugated pi system.
Rank the following in order of deceasing λmax (i.e. decrease in nm):
- A>B>C>D
- D>A>B>C
- A>D>C>B
- B>C>D>A
- D>B>A>C
Which of the following represents a cis isomer of cyclohexane?
Which arrow is used to represent the movement or delocalization of electrons?
- (8 pts) Benzene and cyclohexane are both important 6-membered ring carbon structure that are predominant in pharmaceutical molecules and other molecules of biological interest. Draw the structure for each and then provide 3 chemical facts (i.e. orbitals, hybridization, conformation, etc) for each molecule that indicates the important differences in their structures.
| benzene | cyclohexane |
- (6 pts) Which compound (A or B) is a stronger acid? In each case, circle your answer and provide a very brief explanation for your answer. (In this case, a simple correct phrase is sufficient for your answer…)
- (6 pts) Convert the flat difluorocyclohexane structure shown below to a drawing of a chair conformer. Clearly label if the fluoro groups are axial or equitorial in your chair structure.
- Delocalized electrons and resonance (10 pts total)
- Circle any of the following compounds that have a nitrogen atom with delocalized electrons.
- For each pair of resonance structures shown below (A and B), circle which resonance contributor makes a greater contribution to the resonance hybrid. Briefly explain your answer.
