Laws of Thermodynamics
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Thermodynamics Notes
Thermodynamics Notes Steven K. Krueger Department of Atmospheric Sciences, University of Utah August 2020 Contents 1 Introduction 1 1.1 What is thermodynamics? . .1 1.2 The atmosphere . .1 2 The Equation of State 1 2.1 State variables . .1 2.2 Charles' Law and absolute temperature . .2 2.3 Boyle's Law . .3 2.4 Equation of state of an ideal gas . .3 2.5 Mixtures of gases . .4 2.6 Ideal gas law: molecular viewpoint . .6 3 Conservation of Energy 8 3.1 Conservation of energy in mechanics . .8 3.2 Conservation of energy: A system of point masses . .8 3.3 Kinetic energy exchange in molecular collisions . .9 3.4 Working and Heating . .9 4 The Principles of Thermodynamics 11 4.1 Conservation of energy and the first law of thermodynamics . 11 4.1.1 Conservation of energy . 11 4.1.2 The first law of thermodynamics . 11 4.1.3 Work . 12 4.1.4 Energy transferred by heating . 13 4.2 Quantity of energy transferred by heating . 14 4.3 The first law of thermodynamics for an ideal gas . 15 4.4 Applications of the first law . 16 4.4.1 Isothermal process . 16 4.4.2 Isobaric process . 17 4.4.3 Isosteric process . 18 4.5 Adiabatic processes . 18 5 The Thermodynamics of Water Vapor and Moist Air 21 5.1 Thermal properties of water substance . 21 5.2 Equation of state of moist air . 21 5.3 Mixing ratio . 22 5.4 Moisture variables . 22 5.5 Changes of phase and latent heats . -
31 Jan 2021 Laws of Thermodynamics . L01–1 Review of Thermodynamics. 1
31 jan 2021 laws of thermodynamics . L01{1 Review of Thermodynamics. 1: The Basic Laws What is Thermodynamics? • Idea: The study of states of physical systems that can be characterized by macroscopic variables, usu- ally equilibrium states (mechanical, thermal or chemical), and possible transformations between them. It started as a phenomenological subject motivated by practical applications, but it gradually developed into a coherent framework that we will view here as the macroscopic counterpart to the statistical mechanics of the microscopic constituents, and provides the observational context in which to verify many of its predictions. • Plan: We will mostly be interested in internal states, so the allowed processes will include heat exchanges and the main variables will always include the internal energy and temperature. We will recall the main facts (definitions, laws and relationships) of thermodynamics and discuss physical properties that characterize different substances, rather than practical applications such as properties of specific engines. The connection with statistical mechanics, based on a microscopic model of each system, will be established later. States and State Variables for a Thermodynamical System • Energy: The internal energy E is the central quantity in the theory, and is seen as a function of some complete set of variables characterizing each state. Notice that often energy is the only relevant macroscopic conservation law, while momentum, angular momentum or other quantities may not need to be considered. • Extensive variables: For each system one can choose a set of extensive variables (S; X~ ) whose values specify ~ the equilibrium states of the system; S is the entropy and the X are quantities that may include V , fNig, ~ ~ q, M, ~p, L, .. -
Thermodynamic State Variables Gunt
Fundamentals of thermodynamics 1 Thermodynamic state variables gunt Basic knowledge Thermodynamic state variables Thermodynamic systems and principles Change of state of gases In physics, an idealised model of a real gas was introduced to Equation of state for ideal gases: State variables are the measurable properties of a system. To make it easier to explain the behaviour of gases. This model is a p × V = m × Rs × T describe the state of a system at least two independent state system boundaries highly simplifi ed representation of the real states and is known · m: mass variables must be given. surroundings as an “ideal gas”. Many thermodynamic processes in gases in · Rs: spec. gas constant of the corresponding gas particular can be explained and described mathematically with State variables are e.g.: the help of this model. system • pressure (p) state process • temperature (T) • volume (V) Changes of state of an ideal gas • amount of substance (n) Change of state isochoric isobaric isothermal isentropic Condition V = constant p = constant T = constant S = constant The state functions can be derived from the state variables: Result dV = 0 dp = 0 dT = 0 dS = 0 • internal energy (U): the thermal energy of a static, closed Law p/T = constant V/T = constant p×V = constant p×Vκ = constant system. When external energy is added, processes result κ =isentropic in a change of the internal energy. exponent ∆U = Q+W · Q: thermal energy added to the system · W: mechanical work done on the system that results in an addition of heat An increase in the internal energy of the system using a pressure cooker as an example. -
Nonequilibrium Thermodynamics and Scale Invariance
Article Nonequilibrium Thermodynamics and Scale Invariance Leonid M. Martyushev 1,2,* and Vladimir Celezneff 3 1 Technical Physics Department, Ural Federal University, 19 Mira St., Ekaterinburg 620002, Russia 2 Institute of Industrial Ecology, Russian Academy of Sciences, 20 S. Kovalevskaya St., Ekaterinburg 620219, Russia 3 The Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel; [email protected] * Correspondence: [email protected]; Tel.: +7-92-222-77-425 Academic Editors: Milivoje M. Kostic, Miguel Rubi and Kevin H. Knuth Received: 30 January 2017; Accepted: 14 March 2017; Published: 16 March 2017 Abstract: A variant of continuous nonequilibrium thermodynamic theory based on the postulate of the scale invariance of the local relation between generalized fluxes and forces is proposed here. This single postulate replaces the assumptions on local equilibrium and on the known relation between thermodynamic fluxes and forces, which are widely used in classical nonequilibrium thermodynamics. It is shown here that such a modification not only makes it possible to deductively obtain the main results of classical linear nonequilibrium thermodynamics, but also provides evidence for a number of statements for a nonlinear case (the maximum entropy production principle, the macroscopic reversibility principle, and generalized reciprocity relations) that are under discussion in the literature. Keywords: dissipation function; nonequilibrium thermodynamics; generalized fluxes and forces 1. Introduction Classical nonequilibrium thermodynamics is an important field of modern physics that was developed for more than a century [1–5]. It is fundamentally based on thermodynamics and statistical physics (including kinetic theory and theory of random processes) and is widely applied in biophysics, geophysics, chemistry, economics, etc. -
Basic Thermodynamics-17ME33.Pdf
Module -1 Fundamental Concepts & Definitions & Work and Heat MODULE 1 Fundamental Concepts & Definitions Thermodynamics definition and scope, Microscopic and Macroscopic approaches. Some practical applications of engineering thermodynamic Systems, Characteristics of system boundary and control surface, examples. Thermodynamic properties; definition and units, intensive and extensive properties. Thermodynamic state, state point, state diagram, path and process, quasi-static process, cyclic and non-cyclic processes. Thermodynamic equilibrium; definition, mechanical equilibrium; diathermic wall, thermal equilibrium, chemical equilibrium, Zeroth law of thermodynamics, Temperature; concepts, scales, fixed points and measurements. Work and Heat Mechanics, definition of work and its limitations. Thermodynamic definition of work; examples, sign convention. Displacement work; as a part of a system boundary, as a whole of a system boundary, expressions for displacement work in various processes through p-v diagrams. Shaft work; Electrical work. Other types of work. Heat; definition, units and sign convention. 10 Hours 1st Hour Brain storming session on subject topics Thermodynamics definition and scope, Microscopic and Macroscopic approaches. Some practical applications of engineering thermodynamic Systems 2nd Hour Characteristics of system boundary and control surface, examples. Thermodynamic properties; definition and units, intensive and extensive properties. 3rd Hour Thermodynamic state, state point, state diagram, path and process, quasi-static -
Ch. 3. the Third Law of Thermodynamics (Pdf)
3-1 CHAPTER 3 THE THIRD LAW OF THERMODYNAMICS1 In sharp contrast to the first two laws, the third law of thermodynamics can be characterized by diverse expression2, disputed descent, and questioned authority.3 Since first advanced by Nernst4 in 1906 as the Heat Theorem, its thermodynamic status has been controversial; its usefulness, however, is unquestioned. 3.1 THE HEAT THEOREM The Heat Theorem was first proposed as an empirical generalization based on the temperature dependence of the internal energy change, ∆U, and the Helmholtz free energy change, ∆A, for chemical reactions involving condensed phases. As the absolute temperature, T, approaches zero, ∆U and ∆A by definition become equal, but The Heat Theorem stated that d∆U/dT and d∆A/dT also approach zero. These derivatives are ∆Cv and -∆S respectively. The statement that ∆Cv equals zero would attract little attention today in view of the abundance of experimental and theoretical evidence showing that the heat capacities of condensed phases approach zero as zero absolute temperature is approached. However, even today the controversial and enigmatic aspect of The Heat Theorem is the equivalent statement 1 Most of this chapter is taken from B.G. Kyle, Chem. Eng. Ed., 28(3), 176 (1994). 2 For a sampling of expressions see E. M. Loebl, J. Chem. Educ., 37, 361 (1960). 3 For extreme positions see E. D. Eastman, Chem. Rev., 18, 257 (1936). 4 All of Nernst's work in this area is covered in W. Nernst, The New Heat Theorem; Dutton: New York, 1926. 3-2 lim ∆S = 0 (3-1) T → 0 In 1912 Nernst offered a proof that the unattainability of zero absolute temperature was dictated by the second law of thermodynamics and was able to show that Eq. -
Bsc Chemistry
Subject Chemistry Paper No and Title 10: Physical Chemistry –III (Classical Thermodynamics, Non-Equilibrium Thermodynamics, Surface Chemistry, Fast Kinetics) Module No and Title 12: Thermodynamic criteria for non-equilibrium states Module Tag CHE_P10_M12 CHEMISTRY Paper No. 10: Physical Chemistry –III (Classical Thermodynamics, Non-Equilibrium Thermodynamics, Surface Chemistry, Fast Kinetics) Module No. 12: Thermodynamic criteria for nonequilibrium states TABLE OF CONTENTS 1. Learning Outcomes 2. Introduction 3. Difference between equilibrium and non-equilibrium thermodynamics 4. Postulates of irreversible thermodynamics 5. Non equilibrium state variables 6. Basic concepts 6.1 Zeroth law of thermodynamics 6.2 First law of thermodynamics 6.3 Second law of thermodynamics 6.4 Third law of thermodynamics 7. Summary CHEMISTRY Paper No. 10: Physical Chemistry –III (Classical Thermodynamics, Non-Equilibrium Thermodynamics, Surface Chemistry, Fast Kinetics) Module No. 12: Thermodynamic criteria for nonequilibrium states 1. Learning Outcomes After studying this module you shall be able to: Know the significance of irreversible thermodynamics Differentiate between equilibrium and non-equilibrium thermodynamics. Learn postulates of non-equilibrium thermodynamics. Know about different laws of thermodynamics (first, second and third) laws. 2. Introduction In classical thermodynamics, we have seen time dependent variation of thermodynamic quantities such as is internal energy (U), enthalpy (H), entropy (S),Gibb’s free energy (G) etc. are not considered. Classical thermodynamics deals with transitions from one equilibrium state to another brought about by different mechanical or chemical methods. Non equilibrium thermodynamics is that branch of thermodynamics that deals with the system which are not in thermodynamic equilibrium. But such systems can be described by non-equilibrium state variables which represent an extrapolation of variables used to specify system in thermodynamic equilibrium. -
Thermal Equilibrium State of the World Oceans
Thermal equilibrium state of the ocean Rui Xin Huang Department of Physical Oceanography Woods Hole Oceanographic Institution Woods Hole, MA 02543, USA April 24, 2010 Abstract The ocean is in a non-equilibrium state under the external forcing, such as the mechanical energy from wind stress and tidal dissipation, plus the huge amount of thermal energy from the air-sea interface and the freshwater flux associated with evaporation and precipitation. In the study of energetics of the oceanic circulation it is desirable to examine how much energy in the ocean is available. In order to calculate the so-called available energy, a reference state should be defined. One of such reference state is the thermal equilibrium state defined in this study. 1. Introduction Chemical potential is a part of the internal energy. Thermodynamics of a multiple component system can be established from the definition of specific entropy η . Two other crucial variables of a system, including temperature and specific chemical potential, can be defined as follows 1 ⎛⎞∂η ⎛⎞∂η = ⎜⎟, μi =−Tin⎜⎟, = 1,2,..., , (1) Te m ⎝⎠∂ vm, i ⎝⎠∂ i ev, where e is the specific internal energy, v is the specific volume, mi and μi are the mass fraction and chemical potential for the i-th component. For a multiple component system, the change in total chemical potential is the sum of each component, dc , where c is the mass fraction of each component. The ∑i μii i mass fractions satisfy the constraint c 1 . Thus, the mass fraction of water in sea ∑i i = water satisfies dc=− c , and the total chemical potential for sea water is wi∑iw≠ N −1 ∑()μμiwi− dc . -
History of Thermodynamics Consequences of the Laws Of
International Journal of Pure and Applied Mathematics Volume 119 No. 12 2018, 1675-1683 ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu Special Issue ijpam.eu CONCEPTS OF THERMODYNAMICS Dr.N.Selvi1, Dr. P.Sugumar2 Associate Professor 1 2 Department of Physics, BIST, BIHER, Bharath University, Chennai. [email protected] The branch of science called thermodynamics deals with systems that are able to transfer thermal energy into at least one other form of energy (mechanical, electrical, etc.) or into work. The laws of thermodynamics were developed over the years as some of the most fundamental rules which are followed when a thermodynamic system goes through some sort of energy change. History of Thermodynamics The history of thermodynamics begins with Otto von Guericke who, in 1650, built the world's first vacuum pump and demonstrated a vacuum using his Magdeburg hemispheres[1-6]. Guericke was driven to make a vacuum to disprove Aristotle's long-held supposition that 'nature abhors a vacuum'. Shortly after Guericke, the English physicist and chemist Robert Boyle had learned of Guericke's designs and, in 1656[7-13], in coordination with English scientist Robert Hooke, built an air pump. Using this pump, Boyle and Hooke noticed a correlation between pressure, temperature, and volume[14-19]. In time, Boyle's Law was formulated, which states that pressure and volume are inversely proportional. Consequences of the Laws of Thermodynamics The laws of thermodynamics tend to be fairly easy to state and understand ... so much so that it's easy to underestimate the impact they have[20-25]. -
Thermodynamic Temperature
Thermodynamic temperature Thermodynamic temperature is the absolute measure 1 Overview of temperature and is one of the principal parameters of thermodynamics. Temperature is a measure of the random submicroscopic Thermodynamic temperature is defined by the third law motions and vibrations of the particle constituents of of thermodynamics in which the theoretically lowest tem- matter. These motions comprise the internal energy of perature is the null or zero point. At this point, absolute a substance. More specifically, the thermodynamic tem- zero, the particle constituents of matter have minimal perature of any bulk quantity of matter is the measure motion and can become no colder.[1][2] In the quantum- of the average kinetic energy per classical (i.e., non- mechanical description, matter at absolute zero is in its quantum) degree of freedom of its constituent particles. ground state, which is its state of lowest energy. Thermo- “Translational motions” are almost always in the classical dynamic temperature is often also called absolute tem- regime. Translational motions are ordinary, whole-body perature, for two reasons: one, proposed by Kelvin, that movements in three-dimensional space in which particles it does not depend on the properties of a particular mate- move about and exchange energy in collisions. Figure 1 rial; two that it refers to an absolute zero according to the below shows translational motion in gases; Figure 4 be- properties of the ideal gas. low shows translational motion in solids. Thermodynamic temperature’s null point, absolute zero, is the temperature The International System of Units specifies a particular at which the particle constituents of matter are as close as scale for thermodynamic temperature. -
Thermodynamic State, Specific Heat, and Enthalpy Function 01 Saturated UO Z Vapor Between 3000 Kand 5000 K
Februar 1977 KFK 2390 Institut für Neutronenphysik und Reaktortechnik Projekt Schneller Brüter Thermodynamic State, Specific Heat, and Enthalpy Function 01 Saturated UO z Vapor between 3000 Kand 5000 K H. U. Karow Als Manuskript vervielfältigt Für diesen Bericht behalten wir uns alle Rechte vor GESELLSCHAFT FÜR KERNFORSCHUNG M. B. H. KARLSRUHE KERNFORSCHUNGS ZENTRUM KARLSRUHE KFK 2390 Institut für Neutronenphysik und Reaktortechnik Projekt Schneller Brüter Thermodynamic State, Specific Heat, and Enthalpy Function of Saturated U0 Vapor between 3000 K 2 and 5000 K H. U. Karow Gesellschaft für Kernforschung mbH., Karlsruhe A summarized version of s will be at '7th Symposium on Thermophysical Properties', held the NBS at Gaithe , 1977 Thermodynamic State, Specific Heat, and Enthalpy Function of Saturated U0 2 Vapor between 3000 K and 5000 K Abstract Reactor safety analysis requires knowledge of the thermophysical properties of molten oxide fuel and of the thermal equation-of state of oxide fuel in thermodynamic liquid-vapor equilibrium far above 3000 K. In this context, the thermodynamic state of satu rated U0 2 fuel vapor, its internal energy U(T), specific heats Cv(T) and C (T), and enthalpy functions HO(T) and HO(T)-Ho have p 0 been determined by means of statistical mechanics in the tempera- ture range 3000 K .•• 5000 K. The discussion of the thermodynamic state includes the evaluation of the plasma state and its contri bution to the caloric variables-of-state of saturated oxide fuel vapor. Because of the extremely high ion and electron density due to thermal ionization, the ionized component of the fuel vapor does no more represent a perfect kinetic plasma - different from the nonionized neutral vapor component with perfect gas kinetic behavior up to about 5000 K. -
Chapter 5 the Laws of Thermodynamics: Entropy, Free
Chapter 5 The laws of thermodynamics: entropy, free energy, information and complexity M.W. Collins1, J.A. Stasiek2 & J. Mikielewicz3 1School of Engineering and Design, Brunel University, Uxbridge, Middlesex, UK. 2Faculty of Mechanical Engineering, Gdansk University of Technology, Narutowicza, Gdansk, Poland. 3The Szewalski Institute of Fluid–Flow Machinery, Polish Academy of Sciences, Fiszera, Gdansk, Poland. Abstract The laws of thermodynamics have a universality of relevance; they encompass widely diverse fields of study that include biology. Moreover the concept of information-based entropy connects energy with complexity. The latter is of considerable current interest in science in general. In the companion chapter in Volume 1 of this series the laws of thermodynamics are introduced, and applied to parallel considerations of energy in engineering and biology. Here the second law and entropy are addressed more fully, focusing on the above issues. The thermodynamic property free energy/exergy is fully explained in the context of examples in science, engineering and biology. Free energy, expressing the amount of energy which is usefully available to an organism, is seen to be a key concept in biology. It appears throughout the chapter. A careful study is also made of the information-oriented ‘Shannon entropy’ concept. It is seen that Shannon information may be more correctly interpreted as ‘complexity’rather than ‘entropy’. We find that Darwinian evolution is now being viewed as part of a general thermodynamics-based cosmic process. The history of the universe since the Big Bang, the evolution of the biosphere in general and of biological species in particular are all subject to the operation of the second law of thermodynamics.