CHEM 125a - Lecture 23 - Valence Theory and Constitutional Structure (1858)

Lecture 23 - Valence Theory and Constitutional Structure (1858)


Youthful chemists Couper and Kekulé replaced radical and type theories with a new approach involving atomic valence and molecular structure, and based on the tetravalence and self-linking of carbon. Valence structures offered the first explanation for isomerism, and led to the invention of nomenclature, notation, and molecular models closely related to those in use today.


Professor McBride's web resources for CHEM 125 (Fall 2008)

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Reading assignments, problem sets, PowerPoint presentations, and other resources for this lecture can be accessed from Professor McBride's on-campus course website, which was developed for his Fall 2008 students. Please see Resources section below.

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