n.
In thermodynamics , a chemically and physically uniform quantity of matter that can be separated mechanically from a nonhomogeneous mixture.
It may consist of a single substance or of a mixture of substances. The three basic phases of matter are solid , liquid , and gas ; other phases that are considered to exist include crystalline (see crystal ), colloidal (see colloid ), glass , amorphous, and plasma . The different phases of a pure substance are related to each other in terms of temperature and pressure . For example, if the temperature of a solid is raised enough, or the pressure is reduced enough, it will become a liquid.