Answer:
This diagram represents a phase change graph for water. As temperature increases, the water goes from solid to liquid to gas. This occurs because as temperature increases, so does the kinetic energy of the water molecules. The flat portions of the graph represent when these phase changes occur. At T = 0 °C, water changes from liquid to solid or solid to liquid depending on whether head is being added or removed. At T = 100 °C, water changes from liquid to gas or gas to liquid.
