Abstract
The pronounced vaporization behavior of congruent vaporization is suggested to be somewhat contradictory looking because of the ambiguity of its definition. New definitions are introduced and the meaning of congruent vaporization composition (C. V. C.) and congruently effusing composition (C. E. C.) are explained in terms of thermodynamics. The difference between C. V. C. and C. E. C. is shown by using the experimental results of some refractory compounds.
