CHEM 001 Lecture Notes - Lecture 20: Ammonia, Phosphorus Pentachloride, Antimony Pentachloride

• School: College of The Sequoias
• Department: Chemistry (CHEM)
• Course: CHEM 001
• Professor: guerra

Document Summary

For obvious reasons, this geometry is called linear (180 apart) The central atom"s geometry tells us a molecule"s shape. The geometry of the outer atoms is not needs. The lowest energy arrangement of 3 electron groups around a central atom is 120 apart. The lowest energy arrangement of 4 electron domains around a central atom is 109. 5 apart. Tetrahedrons are pyramids with a triangular base. For tetrahedral arrangements of atoms and/or lone pairs, imagine the atoms inside the tetrahedron and the orbitals pointing toward the vertices. The lowest energy arrangement of 5 electron groups around a central atom is trigonal bipyramidal geometry. Central atoms with 6 electron groups assume octahedral geometry. Vsepr theory - lone pairs take up more space around an atom than bonded electrons. The electron density of lone pairs is hemispherical in shape. The electron density of bonded electrons ( lone pairs) is cylindrical in shape and distributed around the axis of a bond.