CHEM 001B Lecture Notes - Lecture 2: Trigonal Bipyramidal Molecular Geometry, Trigonal Planar Molecular Geometry, Chemical Polarity

• School: UC Riverside
• Department: Chemistry
• Course: CHEM 001B
• Professor: Cheng Quan

Document Summary

Molecules have three-dimensional structure which determines their activity. A model predicting that the arrangement of valence electron pairs around a central. Electron-pair geometry : arrangement of bonding electron pairs and lone pair atom minimizes repulsion to produce the lowest-energy orientation. electrons. Sn = (# atoms bonded to central atom) + (# lone pairs on central atom) Molecular geometry : arrangement of atoms in a molecule. Carbon is the likely central atom of both molecules because it has a bonding capacity of four. The atoms bonded to c are as far from each other as possible. The molecular geometries are consistent with vsepr theory for three and four electron groups. It is worth noting that the c atom always has four bonds, but a double bond counts as only one electron cloud, resulting in a trigonal planar geometry. Three electron pairs (2 bonding + 1 lone pair) Electron pair repulsion! double bond. repulsion between bonding pairs.