26. Which of the following are consistent with the requirements for aromaticity? I. A system with delocalized л electrons in a ring. II. 4n л electrons in the ring. III. All the ring atoms must be carbons. IV. (4n+2) л electrons in the ring. A. I and II AR B. I and IV C. D. I, II, and III I, III, and IV

26. Which of the following are consistent with the requirements for aromaticity? I. A system with delocalized л electrons in a ring. II. 4n л electrons in the ring. III. All the ring atoms must be carbons. IV. (4n+2) л electrons in the ring. A. I and II AR B. I and IV C. D. I, II, and III I, III, and IV

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter21: Benzene And The Concept Of Aromaticity

Section: Chapter Questions

Problem 21.16P: Which of the molecules and ions given in Problem 21.15 are aromatic according to the Hckel criteria?...

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