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Chemistry LibreTexts

2: Conjugation, Resonance, and Aromaticity

  • Page ID
    418216
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    Learning Objectives

    After Chapter 2, you should be able to

    1. identify conjugated and non-conjugated bonding in molecules
    2. use the information presented in this chapter, along with material from earlier chapters, to solve problems, particularly road-map problems and those requiring an understanding of spectroscopy.
    3. explain the concept of aromaticity and the stability of aromatic compounds.
    4. define, and use in context, the key terms introduced.

    In Chapter 2, we describe conjugation within molecules and how it relates to electronic communication. Lewis' method for drawing organic molecules does not always accurately predict some chemical and/or physical phenomenon. Resonance theory is a way to represent molecules as a combination of multiple Lewis structures - the hybrid of which best describes the chemical and physical properties of the molecule. Molecules that are considered aromatic 1) are conjugated, 2) can be represented using a combination of Lewis structures, and 3) have chemical properties that make them uniquely stable.


    2: Conjugation, Resonance, and Aromaticity is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Dietmar Kennepohl.