Chemistry 141 Monday, November 6, 2017 Lecture 26 Chemistry 11 - Lecture 11 9/30/2009 Chemistry 141 Monday, November 6, 2017 Lecture 26 Electron Configurations and Bonding
Electron Configurations 1s2 2s1
Hund’s Rule “For degenerate orbitals, the lowest energy is attained when the number of electrons with the same spin is maximized.”
Periodic Table
Lewis Symbols
Drawing Lewis Structures Sum the valence electrons in the molecule (or ion – correct for charge) Arrange and write the atomic symbols. Connect atoms with a single line to indicate a bond. Use dots to complete octets around the peripheral atoms (except H, which has 2). Place any remaining electrons as lone pairs on the central atom If there are not enough electrons for the central atom to have an octet, try forming multiple bonds. Calculate formal charges: Formal charge = valence electrons – ½ (bonding electrons) – all nonbonding electrons
The Best Lewis Structure? Start here 6/11/10