organic chemstry

Quiz 8 Total points 20 Choose the correct answers ( 2 pts X 10 = 20 pts) 1) Which of the following statements about benzene is correct? A) All the carbon atoms are sp3 hybridized. B) It has no delocalized electrons. C) The carbon-carbon bonds are longer than the carbon-carbon bond in ethane. D) It is a planar molecule. E) The carbon-hydrogen bonds are not the same length. 2) Which of the following is a resonance hybrid? A)

B)

C)

D)

E) A, B, and C. 3) Which of the following does NOT have delocalized electrons? A) allyl cation B) benzyl anion C) CO32- D) benzyl cation E) cyclohexyl radical

4) Which has correctly drawn arrows? A)

B)

C)

D)

E)

5) Which of the following statements about resonance contributors and resonance hybrids is not correct? A) The fewer nearly equivalent resonance contributors, the greater the resonance energy. B) A resonance hybrid is more stable than the predicted stability of any of its resonance contributors. C) The greater the number of relatively stable resonance contributors, the greater the resonance energy. D) The greater the predicted stability of a resonance contributor, the more it contributes to the resonance hybrid. E) none of the above

6) Which of the following is the most stable diene?

A) I B) II C) III D) IV E) V 7)What is the major product of the following reaction?

A)

B) BrCH2CH2CH2CH2CH CH2 C)

D) BrCH2CH2CH2CH2CH2CH2Br E)

8) Which compound has the shortest bond between its two middle carbons? A) CH2 CH—CH CH2 B) CH3CH2—CH CH2 C) CH2 CH—C CH D) CH3CH2—C CH E) CH C—C CH 9) Which of the following is the major product of the following reaction?

A) I B) I and II C) I and III D) II E) III 10) What are the products from the following reaction?

A) I and II B) I and III C) I and IV D) II and III E) II and IV