Adobe acrobat is available on most computers or can be downloaded for free from adobe. Phase equilibria and their applications article pdf available in the european physical journal special topics 2265. Phase equilibria the equilibrium phase is always the one with the lowest free energy g h t s the driving force for a phase change is the minimization of free energy equilibrium state with minimum free energy under some specified combination of temperature, pressure, and composition e. When interpreting a phase diagram it is critical to note that the pressure that is important for the gas is the partial pressure of the substance you are looking at. Physical properties of substances are understood in terms of kineticmolecular theory. Phase equilibria of pure substances atkins, chapter 5 phase transition. Handouts of the lectures two slides per page can be obtained for perusal or printing out by clicking on the appropriate lecture below. What happens when substances change their chemical structure and interchange, and youve figured out how to calculate where equilibrium lies in the case of chemical reactions. While this is a complex and challenging area, the use of computational tools has. In fact, we will spend much of the rest of the course discussing aspects of this concept. Ln10 phase some molecules will reenter the liquid phase and a situation will be established whereby the rate of evaporation will equal the rate of condensation.
If they all intersect, called triple point, three phases in equilibrium. The course seeks to teach students the application of thermodynamics on real problems, how to estimate where basic information is scarce and how to interpret thermodynamic information in the context of case studies. Diffusion and phase equilibria spring 2020 lectures. A system is at equilibrium if at constant temperature. Thus, it is best to think about the pressure in this graph. We will focus on twodimensional systems, but the techniques used here also work in n dimensions. Notes for chemical equilibrium thermodynamics chemical equilibrium understanding how to work problems for chemical equilibrium is one of the most important concepts in secondsemester chemistry. Given the equilibrium constant k eq for a reaction, predict whether the reactants or products are predominant. Cooling curves the method that is used to map the phase boundaries on a phase diagram is to measure the rate of cooling for a sample of known composition. Math 312 lecture notes linearization warren weckesser department of mathematics colgate university 23 march 2005 these notes discuss linearization, in which a linear system is used to approximate the behavior of a nonlinear system. Chemistry notes download handwritten pdf chemistry notes. Phase equilibria, phase diagrams and phase transformations second edition thermodynamic principles are central to understanding material behaviour, particularly as the application of these concepts underpins phase equilibrium, transformation and state.
In fact, there is a road map that, once understood, allows. Equilibria because the concentrations of liquids and solids are constant, they are left out of the equilibrium constant expression. Lecture 1 masc 504 diffusion and phase equilibria masc 504. Given a chemical equation, write the law of mass action.
Mech 6661 thermodynamics of materials and phase equilibria. G ng m 2 ng m 1 ng m 2 g m 1 phase equilibria and phase diagrams phase diagrams are one of the most important sources of information concerning the behavior of elements, compounds and solutions. Say we monitor n 2, and obtain a rate of dn 2 dt x mol dm3 s1. It consists of atoms of at least two different types where solute atoms. It is a part of a system, uniform through out in chemical composition and physical properties, that is separated a uniform component part of the system that is separated from the other homogeneous parts e. For a phase transition, the two phases are in equilibrium. The first module deals with phase diagrams charts that tell us how a material will behave given a certain set of variables such as temperature, pressure, and composition.
Binary liquid mixtures vapor pressure for an ideal binary mixture of two volatile liquids, a and b. They provide us with the knowledge of phase composition and phase stability as. A phase boundary separates the regions and on these lines the phases coexis t in equilibrium i. Chem 340 lecture notes 9 fall 20 phase equilibria chap. Intermolecular forces, liquids, and solids lecture outline 11. Drude theory of metals university of california, irvine. Chapter 10 properties of gases chapter 11 liquids, solids and phase changes chapter 12 solutions and their properties chapter chemical kinetics chapter 14 chemical equilibrium chapter 15 aqueous equilibria. Note that the condition of equilibrium implies that there is a temperature and pressure condition where all these phases have to coexist, this is called the triple point. Similarly, monitoring the concentration of nh 3 would yield a rate of 2x mol dm3 s1.
Derivation of phase rule, brief concept on one and two component system, application of phase rule to three component systems of both solids. Phase diagrams and phase equilibria this course picks up with an overview of basic thermodynamics and kinetics as they pertain to the processing of crystalline materials. Only gases and aqueous phase substances are included. Pdf lecture notes on thermodynamics carlos martinez. We have both general chemistry notes and organic chemistry notes. A phase diagrams is a type of graph used to show the equilibrium conditions between the thermodynamicallydistinct phases.
First law, entropy and free energy, phase equilibria, solutions and chemical equilibrium, electrochemistry, electrolyte solutions and kinetics. At equilibrium, the two phases will have the same free energy. The rate of cooling will change as the sample or some portion of it begins to undergo a phase change. Boiling point and freezing point of solutions dialysis and binding phenomena. The second one, unifac, is a group contribution method gcm but. Use le chateliers principle to explain how a chemical reaction at equilibrium responds when a change is made to the concentration of reactant or. Since for every mole of n 2 that reacts, we lose three moles of h 2, if we had monitored h 2 instead of n 2 we would have obtained a rate dh 2 dt 3x mol dm3 s1. Just as oil and water represent two distinct liquid phases, two regions of a solid with distinctly.
Max concentration for which only a single phase solution occurs. Notes on phase equilibria 2016 cem2005w phase equilibria. So, recently youve been looking at chemical equilibria. A mixture of oil and water would also be a twophase system. It will focus on thermodynamic modeling of phase diagrams. This course emphasizes the application of thermodynamics to understand materials. The brouwer diagram and understanding complex equilibria between defects. This means something from the thermodynamics standpoint. Chapter 8, acidbase equilibria road map of acidbase equilibria on first encounter, the study of acidbase equilibria is a little like a strange land with seemingly confusing trails that make passage difficult. Pressure and scales are nonuniform, schematic only. Phase equilibria and phase diagrams phase diagrams are one of the most important sources of information concerning the behavior of elements, compounds and solutions. Equilibrium phase diagrams represent the relationships between temperature and the compositions.
Phase diagrams in materials science and engineering 183,322 views. Our notes are easytofollow, handwritten chemistry pdf notes that combine your book and chemistry notes into one, simple, easytounderstand format. Summary for chapter 8 phase equilibrium in flemings physical chemistry textmap. Phase equilibria phase equilibria phase equilibrium describes the way phases such as solid, liquid andor gas coexist at some temperatures and pressure, but interchange at others. A phase diagrams show what phases exist at equilibrium. They refer to the independent chemical species that comprise the system. They are available in pdf format which can be accessed using adobe acrobat. Thus, the maximum concentration of a species in an aqueous stream in contact with an organic stream can be estimated by these calculations.
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