We will focus on twodimensional systems, but the techniques used here also work in n dimensions. A phase diagrams show what phases exist at equilibrium. Summary for chapter 8 phase equilibrium in flemings physical chemistry textmap. This course emphasizes the application of thermodynamics to understand materials. Use le chateliers principle to explain how a chemical reaction at equilibrium responds when a change is made to the concentration of reactant or. 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. 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. Thus, the maximum concentration of a species in an aqueous stream in contact with an organic stream can be estimated by these calculations. A phase diagrams is a type of graph used to show the equilibrium conditions between the thermodynamicallydistinct phases. Pressure and scales are nonuniform, schematic only.
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. Our notes are easytofollow, handwritten chemistry pdf notes that combine your book and chemistry notes into one, simple, easytounderstand format. This means something from the thermodynamics standpoint. The second one, unifac, is a group contribution method gcm but. 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. Physical properties of substances are understood in terms of kineticmolecular theory. Derivation of phase rule, brief concept on one and two component system, application of phase rule to three component systems of both solids. So, recently youve been looking at chemical equilibria.
Phase equilibria and their applications article pdf available in the european physical journal special topics 2265. It will focus on thermodynamic modeling of phase diagrams. The rate of cooling will change as the sample or some portion of it begins to undergo a phase change. We have both general chemistry notes and organic chemistry notes. For a phase transition, the two phases are in equilibrium. It consists of atoms of at least two different types where solute atoms. Boiling point and freezing point of solutions dialysis and binding phenomena. Just as oil and water represent two distinct liquid phases, two regions of a solid with distinctly. Chemistry notes download handwritten pdf chemistry notes.
In fact, there is a road map that, once understood, allows. 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. 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. Intermolecular forces, liquids, and solids lecture outline 11. Phase equilibria of pure substances atkins, chapter 5 phase transition. 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. At equilibrium, the two phases will have the same free energy. A phase boundary separates the regions and on these lines the phases coexis t in equilibrium i.
Binary liquid mixtures vapor pressure for an ideal binary mixture of two volatile liquids, a and b. Drude theory of metals university of california, irvine. Given the equilibrium constant k eq for a reaction, predict whether the reactants or products are predominant. Thus, it is best to think about the pressure in this graph. A system is at equilibrium if at constant temperature. While this is a complex and challenging area, the use of computational tools has. 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. In fact, we will spend much of the rest of the course discussing aspects of this concept. If they all intersect, called triple point, three phases in equilibrium. Say we monitor n 2, and obtain a rate of dn 2 dt x mol dm3 s1. 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. Equilibria because the concentrations of liquids and solids are constant, they are left out of the equilibrium constant expression. Diffusion and phase equilibria spring 2020 lectures. 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.
Handouts of the lectures two slides per page can be obtained for perusal or printing out by clicking on the appropriate lecture below. Chem 340 lecture notes 9 fall 20 phase equilibria chap. Adobe acrobat is available on most computers or can be downloaded for free from adobe. 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. 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. Phase equilibria and phase diagrams phase diagrams are one of the most important sources of information concerning the behavior of elements, compounds and solutions. 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. 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. Lecture 1 masc 504 diffusion and phase equilibria masc 504. 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. First law, entropy and free energy, phase equilibria, solutions and chemical equilibrium, electrochemistry, electrolyte solutions and kinetics. Only gases and aqueous phase substances are included.
A mixture of oil and water would also be a twophase system. Pdf lecture notes on thermodynamics carlos martinez. They provide us with the knowledge of phase composition and phase stability as. Similarly, monitoring the concentration of nh 3 would yield a rate of 2x mol dm3 s1. 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. Notes on phase equilibria 2016 cem2005w phase equilibria. Equilibrium phase diagrams represent the relationships between temperature and the compositions. Given a chemical equation, write the law of mass action.
Phase diagrams in materials science and engineering 183,322 views. Max concentration for which only a single phase solution occurs. 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. 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. The brouwer diagram and understanding complex equilibria between defects. They refer to the independent chemical species that comprise the system. They are available in pdf format which can be accessed using adobe acrobat.
936 1039 155 647 768 1045 223 1256 1048 1002 602 1385 1038 269 467 932 862 480 108 1234 495 747 421 422 1246 593 702 1111 1259 26 770 36 1192 356 979 479 821 244 652 457 652 181