What is a phase change diagram?

Phase diagram is a graphical representation of the physical states of a substance under different conditions of temperature and pressure. A typical phase diagram has pressure on the y-axis and temperature on the x-axis. As we cross the lines or curves on the phase diagram, a phase change occurs.

What is sublimation in phase change?

Sublimation is the transition of a substance directly from the solid phase to the gas phase without passing through the intermediate liquid phase (Table 4.8, Fig. 4.2). Sublimation is an endothermic phase transition that occurs at temperatures and pressures below the triple point of a chemical in the phase diagram.

What is a phase change diagram and what is it used for?

Phase diagrams are used to show when a specific substance will change its state of matter (alignment of particles and distance between particles).

What are the 6 types of phase changes?

Sublimation, deposition, condensation, evaporation, freezing, and melting represent phase changes of matter.

How do you describe a phase change?

A phase change is when matter changes to from one state (solid, liquid, gas, plasma) to another. (see figure 1). These changes occur when sufficient energy is supplied to the system (or a sufficient amount is lost), and also occur when the pressure on the system is changed.

What do phase diagrams show?

A phase diagram is a graph which shows under what conditions of temperature and pressure distinct phases of matter occur. The triple point is the point on the phase diagram where the lines of equilibrium intersect — the point at which all three distinct phases of matter ( solid, liquid, gas) coexist.

How are phase diagrams created?

A phase diagram is constructed by preparing alloys of required constituents, heat treating at high temperatures to reach equilibrium states, and then identifying the phases, so as to determine liquidus temperatures, solidus temperatures, solubility lines, and other phase transition lines [1,2].

What is sublimation with diagram?

Sublimation is an endothermic process that occurs at temperatures and pressures below a substance’s triple point in its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid.

What is an example of a phase diagram?

An example of a commonly used phase diagram is the iron-carbon phase diagram, which is used to understand the phases present in steel. The amount of carbon present in an iron-carbon alloy, in weight percent, is plotted on the x-axis and temperature is plotted on the y-axis.

What is the use of phase diagrams?

Key Points Phase diagrams can be used to understand the range of thermodynamic variables over which a pure sample of matter exists as a particular state/phase. Phase diagrams are divided into three single phase regions that cover the pressure – temperature space over which the matter being evaluated exists: liquid, gaseous, and solid states. Phase diagrams can be used to understand under which conditions a pure sample of matter exists in two or three state equilibrium, by examining the phase boundaries and the triple

What is phase diagram in chemistry?

Phase diagram. Jump to navigation Jump to search. A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions (pressure, temperature, volume, etc.) at which thermodynamically distinct phases (such as solid, liquid or gaseous states) occur and coexist at equilibrium.