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University Of Pennsylvania College of General Studies Professor William A. Price, Ph.D. CHEM 241-601. Organic Chemistry , 9 th Edition By T.W. Graham Solomons. From the Bark of the Pacific Yew Tree. Introduction: Structure and Bonding. Atomic structure Lewis Structures Resonance
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University Of PennsylvaniaCollege of General StudiesProfessor William A. Price, Ph.D.CHEM 241-601 Organic Chemistry, 9th Edition By T.W. Graham Solomons
Introduction: Structure and Bonding Atomic structure Lewis Structures Resonance Structural Formulas Acids and Bases
All Have the Same GeometryAll Have 4 Regions of Electron Density
Both Resonance Structures Contribute to the Actual Structure
Resonance Rules • Cannot break single (sigma) bonds • Only electrons move, not atoms 3 possibilities: • Lone pair of e- to adjacent bond position • Forms p bond - p bond to adjacent atom - p bond to adjacent bond position
Resonance Stabilization of IonsPos. charge is “delocalized”
Propose Lewis Structures • H2CO2 b) O3 c) N2O d) NH3O e) C2H3ClO f) C2H5NO
Problem Draw [NO2]+ and [NO2]-. Which ion has a “localized” charge and which has a “delocalized” charge. Explain.