A revised set of E, C, T parameters have been obtained by employing a larger data set of enthalpies. The impact of the transfer term on the qualitative discussion of bond strengths is detailed. Procedures are described for using these parameters as a reactivity scale. An example is offered to illustrate the use of these parameters to evaluate the results from a quantum mechanical calculation of bond strengths. -Delta H = E(ca)E(an) + CcaCan + T-ca R(an)