CHEM 1E03 Lecture Notes - Lecture 10: Coordinate Covalent Bond, Electron Shell, Covalent Bond

• School: McMaster University
• Department: Chemistry
• Course: CHEM 1E03
• Professor: Peter Kruse

Document Summary

Chapter 10: lewis theory, electrons, especially those of the outermost (valence) electronic shell, play a fundamental role in chemical bonding, in some cases electrons are transferred from one atom to another. Positive and negative ions are formed and attract each other through electrostatic forces called ionic bonds: in other cases, one or more pairs of electrons are shared between atoms. A bond formed by the sharing of electrons between atoms is called a covalent bond: electrons are transferred or shared in such a way that each atom acquires an especially stable electron configuration. Electron pairs assume orientations about an atom to minimize repulsions: electron group geometries. Three electron groups: trigonal- planar; ax3, ax2e. Four electron groups: tetrahedral; ax4 , ax3e , ax2e2. Five electron groups: trigonal bipyramidal; ax5, ax4eb, ax3e2, Only valence electrons of central atoms influence the molecular shape. Bonded pairs and lone pairs are treated equally (approximately) Valence shell electron pairs repel each other electrostatically.