There are a few important features of a substance that can be deduced from a careful examination of its phase diagram. For each of the qualities given below, described for a substance at room temperature and standard pressure (300 K, 1 bar), come up with a phase diagram feature that would help you identify whether or not it is present. Example: The substance is a liquid. Feature: The liquid-vapor coexistence curve crosses the horizontal line at 1 bar(or atm) at a temperature above 300 K and the triple point exists at a pressure below 1 bar(or atm). (a) The solid phase of the substance does not melt, but sublimes.
(b) The substance can exist in more than one solid phase
.(c) The substance exists as a supercritical fluid.
(d) The liquid phase of the substance is denser than the solid phase.