Chapter 8, Problem 8.12NP

Interpretation Introduction

Interpretation: Whether the given P-T diagrams are for pure substances or not needs to be determined and the features of the diagram that cannot be observed needs to be explained.

Concept Introduction:All substances can mainly exist in three phases; solid, liquid and gas. These three phases can convert into each other by the application of temperature and pressure such as heating of solid leads to the conversion to liquid and then gaseous state of matter.

Similarly, the gases can be compressed at high pressure to liquefy. The interconversion of three phases of substance can be shown on the phase diagram. A triple point indicates the value of T and P at which all the three phases of a substance that is pressure, temperature and volume coexist. At this point, the fusion, sublimation and vaporization curve intersect each other.