Prof. McBride, J. Michael, CHEM 125a, Freshman Organic Chemistry I, Fall 2008, YALE Open Courses: Yale University, Chemistry (Accessed 12/09/2014), http://oyc.yale.edu/chemistry/chem-125a/lecture-13 License: Creative Commons BY-NC-SA Professor McBride uses this lecture to show that covalent bonding depends primarily on two factors: orbital overlap and energy-match. First he discusses how overlap depends on hybridization; then how bond strength depends on the number of shared electrons. In this way quantum mechanics shows that Coulomb's law answers Newton's query about what "makes the Particles of Bodies stick together by very strong Attractions." Energy mismatch between the constituent orbitals is shown to weaken the influence of their overlap. The predictions of this theory are confirmed experimentally by measuring the bond strengths of H-H and H-F during heterolysis and homolysis.