Unfortunately, this may be misleading and cause confusion to some students. Namely, it is known that the enthalpy of vaporization is a positive, temperature dependent quantity that goes to zero at the critical point. Likewise, the change in compressibility upon vaporization is approximately one at low temperatures, but goes to zero at the critical point. In the present manuscript we encourage use of a single assumption that the enthalpy of vaporization relative to the change in compressibility upon vaporization is constant. This is motivated by use of the freely available reference data from "Thermophysical Properties of Fluid Systems" by NIST and with MATLAB code (or MS Excel template) accompanying the electronic version of this manuscript which may be integrated into the undergraduate course. We have shown that this is superior to the conventional explanation, in addition to being simpler.