CHEM 107 Lecture 9: Chapter 9 - Molecular Geometry

• School: Binghamton University
• Department: Chemistry
• Course: CHEM 107
• Professor: Benjamin Turnpenny

Document Summary

Maximizing space between electrons (max. attractions, min. repulsions) Vsper theory: geometric arrangement of electrons based on minimizing repulsion. Electron pair geometry: spatial arrangement of bonding e- pairs and lone pairs (non- bonding) Molecular geometry: de ned by relative arrangement of atoms (bonding pairs) in molecules, based on e- pair geometry, does not take into account of lone-pair electrons, focuses only on bonded central atoms. Steric number: #pairs e- and how they"ll repel each other. In trigonal bipyramid: lone pairs are in equatorial position and it minimizes 90 degree angles. Lone pairs have max repulsion, occupy the most space, bonding pair have least repulsion. Bond angles decrease as lone pairs increase bec lone pairs push down on atoms. Dipole moment: measures degree of charge separation in molecule. Polar molecules: polar bonds (e- density is being pushed, orientation of polar bonds result in charge separation, nonzero diplomat movements, look at electronegativity and electron density.