CPB 314 Lecture 9: CPB 314 (9)
9 Mar 2017
School
Department
Course
Professor
Document Summary
The variations of properties during phase-change processes are best studied and understood with the help of property diagrams such as the t-v, p-v, and p-t diagrams for pure substances. Compressed liquid region saturated liquid line saturated vapor line. At triple-point pressure and temperature, a substance exists in three phases in equilibrium. Sublimation: passing from the solid phase directly into the vapor phase. At low pressures (below the triple-point value), solids evaporate without melting first (sublimation). The p-v-t surfaces present a great deal of information at once, but in a thermodynamic analysis it is more convenient to work with two- dimensional diagrams, such as the p-v and t-v diagrams. For most substances, the relationships among thermodynamic properties are too complex to be expressed by simple equations. Frequently presented in the form of tables. Some thermodynamic properties can be measured, others need to be calculated by using the relations between them and measurable properties.
