CHM 11500 Lecture Notes - Lecture 17: Vsepr Theory, Lone Pair, Lewis Structure

• School: Purdue University
• Department: Chemistry
• Course: CHM 11500
• Professor: Chittaranjan Das

Document Summary

Chm 115 - lecture 17 - vsepr theory. Valence shell electron repulsion theory is a theory used for predicting the shapes of molecules. In order to determine the molecular geometry of a molecule, first draw the lewis structure, which will allow you to determine the number of lone pairs of electrons and bonding pairs of electrons on the central atom. Identify the number of regions of electron density. These regions include lone pairs and bonding pairs. Double bonds count as one region of electron density. Use the number of regions of electron density to determine the electron geometry. Take into account the number of lone pairs to determine the molecular shape. 2 regions of electron density result in a linear geometry with a bond angle of 180 degrees. 3 regions of electron density result in a trigonal planar geometry with bond angles of 120 degrees. 4 regions of electron density result in a tetrahedral geometry with bond angles of.