Molecular models with free rotation

Abstract

A new type of molecular model is described in which the wooden spheres representing atoms are joined together by snap fasteners which permit free rotation, but at the same time hold the model securely together. Details are given for making such models including methods of obtaining tetrahedral angles for the bonds. Models made in this way serve to increase our understanding not only of structural relationships, but of possible molecular motions. MOLECULAR models such as those commonly used for instructional purposes in elementary organic chemistry are constructed of wooden spheres held together by short, removable wooden pegs.

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Improving a Lecture-Size Molecular Model Set by Repurposing Used Whiteboard Markers

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