The First Law of Thermodynamics
|
|
- Melinda Harper
- 6 years ago
- Views:
Transcription
1 Thermodynamics The First Law of Thermodynamics Thermodynamic Processes (isobaric, isochoric, isothermal, adiabatic) Reversible and Irreversible Processes Heat Engines Refrigerators and Heat Pumps The Carnot Cycle Entropy (The Second Law of Thermodynamics) The Third Law of Thermodynamics 1
2 The Zeroth Law of Thermodynamics If A is in thermal equilibrium with C and B in thermal equilibrium i with C then A and B have to be in thermal equilibrium. No heat flows! 2
3 Internal Energy From In thermodynamics, the internal energy of a thermodynamic system, or a body with well-defined boundaries, denoted by U, or sometimes E, is the total of the kinetic energy due to the motion of molecules (translational, rotational, vibrational) and the potential energy associated with the vibrational and electric energy of atoms within molecules or crystals. It includes the energy in all the chemical bonds, and the energy of the free, conduction electrons in metals. 3
4 The First Law of Thermodynamics The first law of thermodynamics says the change in internal energy of a system is equal to the heat flow into the system plus the work done on the system. ΔU Q W 4
5 First Law of Thermodynamics The change in a systems internal energy is related to the heat and the work. ΔU U f U i Q W Where: U f internal energy of end U i internal energy of start Q net thermal energy flowing into system during process Positive when system gains heat Negative when system loses heat W net work done by the system Positive when work done by the system Negative when work done on the system 5
6 Thermodynamic Processes A state variable describes the state of a system at time t, but it does not reveal how the system was put into that state. Examples of state variables: pressure, temperature, volume, number of moles, and internal energy. Thermal processes can change the state of a system. We assume that thermal processes have no friction or other dissipative forces. In other words: All processes are reversible (Reversible means that it is possible to return system and surroundings to the initial states) REALITY: irreversible 6
7 Humpty Dumpty sat on a wall. Humpty Dumpty had a great fall All the king s horses and all the king s men Couldn t put Humpty Dumpty together again * Martin Schullinger-Krause (PH202 Winter 2008) 7
8 A PV diagram can be used to represent the state changes of a system, provided the system is always near equilibrium. The area under a PV curve gives the magnitude of the work done on a system. W<0 for compression and W>0 for expansion. 8
9 To go from the state (V i, P i ) by the path (a) to the state (V f, i i f P f ) requires a different amount of work then by path (b). To return to the initial point (1) requires the work to be nonzero. The work done on a system depends on the path taken in the PV diagram. The work done on a system during a closed cycle can be nonzero. 9
10 An isothermal process implies that both P and V of the gas change (PV T). 10
11 Specific Heats under constant pressure and constant volume Specific heat Q m c ΔT For a gas we use Molar specific heat Q n C ΔT Constant Volume: C V Constant Pressure : C P 11
12 Thermodynamic Processes for an Ideal Gas No work is done on a system when its volume remains constant (isochoric process). For an ideal gas (provided the number of moles remains constant), Q W Q the change in internal ΔU n V ΔT energy is ΔU 0 Q C 12
13 For a constant pressure e (isobaric) process, the change in internal energy is Δ U Q W where W PΔV nrδt and Q nc P Δ T. C P is the molar specific heat at constant pressure. For an ideal gas C P C V +R. 13
14 For a constant temperature (isothermal) process, ΔU 0 and the work done on an ideal gas is V V nrt V V NkT W i i. ln ln f f W Q U i i Δ 0 14
15 We have found for a monoatomic gas ΔU 3/2nRΔT Constant volume: ΔU Q 3/2 n R ΔT n C V ΔT C V 3/2 R Constant pressure: Q ΔU + W n C P ΔT 3/2 n R ΔT + n R ΔT C P 5/2 R C V C P R (always valid for any ideal gas) 15
16 Adiabatic ( not passable ) processes (no heat is gained or lost by the system Q0 0, i.e. system perfectly isolated ) Q0 and so ΔU -W P V constant (isothermal) P V γ constant (adiabatic) γ C P /C V For a monoatomic gas therefore γ 5/3 16
17 Example: An ideal gas is in contact with a heat reservoir so that it remains at constant temperature of K. The gas is compressed from a volume of 24.0 L to a volume of 14.0 L. During the process, the mechanical device pushing the piston to compress the gas is found to expend 5.00 kj of energy. How many moles of the ideal gas are in the system? How much heat flows between the heat reservoir and the gas, and in what direction does the heat flow occur? W nrt V f W 5000J ln( ) n V V i f 8.31 ln(14/ 24) RT ln( ) V i 3.7 mol This is an isothermal process, so ΔU Q - W 0 (for an ideal gas) and W Q kj. Heat flows from the gas to the reservoir. 20
18 An ice cube placed on a countertop in a warm room will melt. The reverse process cannot occur: an ice cube will not form out of the puddle of water on the countertop in a warm room. 21
19 Any process that involves dissipation of energy is not reversible. Any process that involves heat transfer from a hotter object to a colder object is not reversible. The second law of thermodynamics (Clausius Statement): Heat never flows spontaneously from a colder body to a hotter body. 22
20 Heat Engines A heat engine is a device designed to convert disordered energy into ordered energy. The net work done by an engine during one cycle is equal to the net heat flow into the engine during the cycle (ΔU 0). W Q net Q net 23
21 e The efficiency of an engine is defined as net work done by the engine heat input W net Q H (e.g. a efficiency of e0.8 means 80% of the heat is converted to mechanical work) net work output W e heat input Q QH QC QC 1. Q H Q H Note: Q net Q in - Q out net H 24
22 Refrigerators and Heat Pumps Here, heat flows from cold to hot but with work as the input. Pump Refrigerator K Coefficient of performance 25
23 26
24 Reversible Engines and Heat Pumps A reversible engine can be used as an engine (heat input from a hot reservoir and exhausted to a cold reservoir) or as a heat pump (heat is taken from cold reservoir and exhausted to a hot reservoir). 28
25 From the second law of thermodynamics, no engine can have an efficiency ygreater than that of an ideal reversible engine Carnot engine that uses the same two reservoirs. The efficiency of this ideal reversible engine is e r T 1 C. T H 29
26 Details of the Carnot Cycle The ideal engine of the previous section is known as a Carnot engine. The Carnot cycle has four steps: 1. Isothermal expansion: takes in heat from hot reservoir; keeping the gas temperature at T H. 2. Adiabatic expansion: the gas does work without heat flow into the gas; gas temperature decreases to T C. 3. Isothermal compression: Heat Q C is exhausted; gas temperature remains at T C. 4. Adiabatic compression: raises the temperature back to T H. 30
27 The Carnot engine model was graphically expanded upon by Benoit Paul Émile Clapeyron in 1834 and mathematically elaborated upon by Rudolf Clausius in the 1850s and 60s from which the concept of entropy emerged The Carnot cycle illustrated 31
28 The Otto cycle Its power cycle consists of adiabatic compression, heat addition at constant volume, adiabatic expansion and rejection of heat at constant volume and characterized by four strokes, or reciprocating movements of a piston in a cylinder: intake/induction stroke compression stroke power stroke exhaust stroke 32
29 Entropy Heat flows from objects of high temperature to objects at low temperature because this process increases the disorder of the system. Entropy is a measure of a system s disorder. Entropy is a state variable. 35
30 If an amount of heat Q flows into a system at constant temperature, then the change in entropy is Q ΔSS. T Every irreversible ibl process increases the total t entropy of the universe. Reversible processes do not increase the total entropy of the universe. 36
31 The second law of thermodynamics (Entropy Statement): The entropy of the universe never decreases. 37
32 Example: An ice cube at 0.0 C is slowly melting. What is the change in the ice cube s entropy for each 1.00 g of ice that melts? To melt ice requires Q ml f joules of heat. To melt one gram of ice requires J of energy. The entropy change is ΔS Q T J 273 K 1.22 J/K. 38
33 300K Δ Δ S ht hot S cold Q T Q T 300 J 1J/K. 300 K J 60 J/K. 5 K Q 5 K t / t h? tf23tq 39
34 Statistical Interpretation of Entropy A microstate specifies the state of each constituent particle in a thermodynamic system. A macrostate is determined by the values of the thermodynamic state variables. 40
35 probabilit y of a macrostate number of microstates corresponding to the macrostate total number of microstates for all possible macrostates 41
36 The number of microstates for a given macrostate is related to the entropy. S k ln Ω where Ω is the number of microstates. 42
37 The Third Law of Thermodynamics It is impossible to cool a system to absolute zero. 46
Physics 150. Thermodynamics. Chapter 15
Physics 150 Thermodynamics Chapter 15 The First Law of Thermodynamics Let s consider an ideal gas confined in a chamber with a moveable piston If we press the piston è the gas in the chamber compresses
More informationHeat What is heat? Work = 2. PdV 1
eat What is heat? eat (Q) is the flow or transfer of energy from one system to another Often referred to as heat flow or heat transfer Requires that one system must be at a higher temperature than the
More informationChapter 12 Thermodynamics
Chapter 12 Thermodynamics 12.1 Thermodynamic Systems, States, and Processes System: definite quantity of matter with real or imaginary boundaries If heat transfer is impossible, the system is thermally
More informationChapter 12. The Laws of Thermodynamics
Chapter 12 The Laws of Thermodynamics First Law of Thermodynamics The First Law of Thermodynamics tells us that the internal energy of a system can be increased by Adding energy to the system Doing work
More informationChapter 20. Heat Engines, Entropy and the Second Law of Thermodynamics. Dr. Armen Kocharian
Chapter 20 Heat Engines, Entropy and the Second Law of Thermodynamics Dr. Armen Kocharian First Law of Thermodynamics Review Review: The first law states that a change in internal energy in a system can
More informationThe first law of thermodynamics. U = internal energy. Q = amount of heat energy transfer
Thermodynamics Investigation of the energy transfer by heat and work and how natural systems behave (Q) Heat transfer of energy due to temp differences. (W) Work transfer of energy through mechanical means.
More informationKinetic Theory continued
Chapter 12 Kinetic Theory continued 12.4 Kinetic Theory of Gases The particles are in constant, random motion, colliding with each other and with the walls of the container. Each collision changes the
More informationKinetic Theory continued
Chapter 12 Kinetic Theory continued 12.4 Kinetic Theory of Gases The particles are in constant, random motion, colliding with each other and with the walls of the container. Each collision changes the
More informationChapter 12. The Laws of Thermodynamics. First Law of Thermodynamics
Chapter 12 The Laws of Thermodynamics First Law of Thermodynamics The First Law of Thermodynamics tells us that the internal energy of a system can be increased by Adding energy to the system Doing work
More informationThermodynamic Systems, States, and Processes
Thermodynamics Thermodynamic Systems, States, and Processes A thermodynamic system is described by an equation of state, such as the ideal gas law. The location of the state can be plotted on a p V diagram,
More informationUniversity Physics (Prof. David Flory) Chapt_21 Monday, November 26, 2007 Page 1
University Physics (Prof. David Flory) Chapt_21 Monday, November 26, 2007 Page 1 Name: Date: 1. Let k be the Boltzmann constant. If the configuration of the molecules in a gas changes so that the multiplicity
More informationChapter 16 Thermodynamics
Nicholas J. Giordano www.cengage.com/physics/giordano Chapter 16 Thermodynamics Thermodynamics Introduction Another area of physics is thermodynamics Continues with the principle of conservation of energy
More information12 The Laws of Thermodynamics
June 14, 1998 12 The Laws of Thermodynamics Using Thermal Energy to do Work Understanding the laws of thermodynamics allows us to use thermal energy in a practical way. The first law of thermodynamics
More informationHandout 12: Thermodynamics. Zeroth law of thermodynamics
1 Handout 12: Thermodynamics Zeroth law of thermodynamics When two objects with different temperature are brought into contact, heat flows from the hotter body to a cooler one Heat flows until the temperatures
More informationHandout 12: Thermodynamics. Zeroth law of thermodynamics
1 Handout 12: Thermodynamics Zeroth law of thermodynamics When two objects with different temperature are brought into contact, heat flows from the hotter body to a cooler one Heat flows until the temperatures
More informationSpeed Distribution at CONSTANT Temperature is given by the Maxwell Boltzmann Speed Distribution
Temperature ~ Average KE of each particle Particles have different speeds Gas Particles are in constant RANDOM motion Average KE of each particle is: 3/2 kt Pressure is due to momentum transfer Speed Distribution
More informationClass 22 - Second Law of Thermodynamics and Entropy
Class 22 - Second Law of Thermodynamics and Entropy The second law of thermodynamics The first law relates heat energy, work and the internal thermal energy of a system, and is essentially a statement
More informationChapter 19. Heat Engines
Chapter 19 Heat Engines Thermo Processes Eint = Q+ W Adiabatic No heat exchanged Q = 0 and E int = W Isobaric Constant pressure W = P (V f V i ) and E int = Q + W Isochoric Constant Volume W = 0 and E
More informationChapter 20 The Second Law of Thermodynamics
Chapter 20 The Second Law of Thermodynamics When we previously studied the first law of thermodynamics, we observed how conservation of energy provided us with a relationship between U, Q, and W, namely
More information(prev) (top) (next) (Throughout, we will assume the processes involve an ideal gas with constant n.)
1 of 9 8/22/12 9:51 PM (prev) (top) (next) Thermodynamics 1 Thermodynamic processes can be: 2 isothermal processes, ΔT = 0 (so P ~ 1 / V); isobaric processes, ΔP = 0 (so T ~ V); isovolumetric or isochoric
More informationHeat Machines (Chapters 18.6, 19)
eat Machines (hapters 8.6, 9) eat machines eat engines eat pumps The Second Law of thermodynamics Entropy Ideal heat engines arnot cycle Other cycles: Brayton, Otto, Diesel eat Machines Description The
More informationT s change via collisions at boundary (not mechanical interaction)
Lecture 14 Interaction of 2 systems at different temperatures Irreversible processes: 2nd Law of Thermodynamics Chapter 19: Heat Engines and Refrigerators Thermal interactions T s change via collisions
More informationPhysics 1501 Lecture 37
Physics 1501: Lecture 37 Todays Agenda Announcements Homework #12 (Dec. 9): 2 lowest dropped Midterm 2 in class Wednesday Friday: review session bring your questions Todays topics Chap.18: Heat and Work»
More informationQuiz C&J page 365 (top), Check Your Understanding #12: Consider an ob. A) a,b,c,d B) b,c,a,d C) a,c,b,d D) c,b,d,a E) b,a,c,d
Quiz on Chapter 12 Quiz 10 1. C&J page 365 (top), Check Your Understanding #12: Consider an ob A) a,b,c,d B) b,c,a,d C) a,c,b,d D) c,b,d,a E) b,a,c,d Quiz 10 1. C&J page 365 (top), Check Your Understanding
More informationPhysics 121, April 24. Heat and the First Law of Thermodynamics. Department of Physics and Astronomy, University of Rochester
Physics 121, April 24. Heat and the First Law of Thermodynamics. Physics 121. April 24, 2008. Course Information Topics to be discussed today: Heat First law of thermodynamics Second law of thermodynamics
More informationAP PHYSICS 2 WHS-CH-15 Thermodynamics Show all your work, equations used, and box in your answers!
AP PHYSICS 2 WHS-CH-15 Thermodynamics Show all your work, equations used, and box in your answers! Nicolas Léonard Sadi Carnot (1796-1832) Sadi Carnot was a French military engineer and physicist, often
More informationPhysics 121, April 24. Heat and the First Law of Thermodynamics. Physics 121. April 24, Physics 121. April 24, Course Information
Physics 121, April 24. Heat and the First Law of Thermodynamics. Physics 121. April 24, 2008. Course Information Topics to be discussed today: Heat First law of thermodynamics Second law of thermodynamics
More informationLecture 26. Second law of thermodynamics. Heat engines and refrigerators.
ecture 26 Second law of thermodynamics. Heat engines and refrigerators. The Second aw of Thermodynamics Introduction The absence of the process illustrated above indicates that conservation of energy is
More informationThe first law of thermodynamics continued
Lecture 7 The first law of thermodynamics continued Pre-reading: 19.5 Where we are The pressure p, volume V, and temperature T are related by an equation of state. For an ideal gas, pv = nrt = NkT For
More informationPhysics 231. Topic 14: Laws of Thermodynamics. Alex Brown Dec MSU Physics 231 Fall
Physics 231 Topic 14: Laws of Thermodynamics Alex Brown Dec 7-11 2015 MSU Physics 231 Fall 2015 1 8 th 10 pm correction for 3 rd exam 9 th 10 pm attitude survey (1% for participation) 10 th 10 pm concept
More informationChapter 20 Second Law of Thermodynamics. Copyright 2009 Pearson Education, Inc.
Chapter 20 Second Law of Thermodynamics It is easy to produce thermal energy using work, but how does one produce work using thermal energy? This is a heat engine; mechanical energy can be obtained from
More informationEntropy & the Second Law of Thermodynamics
PHYS102 Previous Exam Problems CHAPTER 20 Entropy & the Second Law of Thermodynamics Entropy gases Entropy solids & liquids Heat engines Refrigerators Second law of thermodynamics 1. The efficiency of
More informationHow to please the rulers of NPL-213 the geese
http://www.walkingmountains. org/2015/03/reintroduction-ofthe-canada-goose/ How to please the rulers of NPL-213 the geese (Entropy and the 2 nd Law of Thermodynamics) Physics 116 2017 Tues. 3/21, Thurs
More informationLaws of Thermodynamics
Laws of Thermodynamics The Three Laws of Thermodynamics - The first lawof thermodynamics, also called conservation of energy. We can use this knowledge to determine the amount of energy in a system, the
More informationΔU = Q W. Tue Dec 1. Assign 13/14 Friday Final: Fri Dec 11 2:30PM WALTER 145. Thermodynamics 1st Law. 2 nd Law. Heat Engines and Refrigerators
Tue Dec 1 Thermodynamics 1st Law ΔU = Q W 2 nd Law SYS Heat Engines and Refrigerators Isobaric: W = PΔV Isochoric: W = 0 Isothermal: ΔU = 0 Adiabatic: Q = 0 Assign 13/14 Friday Final: Fri Dec 11 2:30PM
More informationLecture Outline Chapter 18. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.
Lecture Outline Chapter 18 Physics, 4 th Edition James S. Walker Chapter 18 The Laws of Thermodynamics Units of Chapter 18 The Zeroth Law of Thermodynamics The First Law of Thermodynamics Thermal Processes
More information11/29/2017 IRREVERSIBLE PROCESSES. UNIT 2 Thermodynamics: Laws of thermodynamics, ideal gases, and kinetic theory
11/9/017 AP PHYSICS UNIT Thermodynamics: Laws of thermodynamics, ideal gases, and kinetic theory CHAPTER 13 SECOND LAW OF THERMODYNAMICS IRREVERSIBLE PROCESSES The U G of the water-earth system at the
More informationPhysics 202 Homework 5
Physics 202 Homework 5 Apr 29, 2013 1. A nuclear-fueled electric power plant utilizes a so-called boiling water reac- 5.8 C tor. In this type of reactor, nuclear energy causes water under pressure to boil
More informationPhysics 101: Lecture 28 Thermodynamics II
Physics 101: Lecture 28 Thermodynamics II Final Today s lecture will cover Textbook Chapter 15.6-15.9 Check Final Exam Room Assignment! Bring ID! Be sure to check your gradebook! Physics 101: Lecture 28,
More informationTHERMODYNAMICS CONCEPTUAL PROBLEMS
THERMODYNAMICS CONCEPTUAL PROBLEMS Q-01 Is the heat supplied to a system always equal to the increases in its internal energy? Ans Acc. to first law of thermo- dynamics If heat is supplied in such a manner
More informationTemperature Thermal Expansion Ideal Gas Law Kinetic Theory Heat Heat Transfer Phase Changes Specific Heat Calorimetry Heat Engines
Temperature Thermal Expansion Ideal Gas Law Kinetic Theory Heat Heat Transfer Phase Changes Specific Heat Calorimetry Heat Engines Zeroeth Law Two systems individually in thermal equilibrium with a third
More informationThe laws of Thermodynamics. Work in thermodynamic processes
The laws of Thermodynamics ork in thermodynamic processes The work done on a gas in a cylinder is directly proportional to the force and the displacement. = F y = PA y It can be also expressed in terms
More informationChapter 19. Heat Engines
Chapter 19 Heat Engines QuickCheck 19.11 The efficiency of this Carnot heat engine is A. Less than 0.5. B. 0.5. C. Between 0.5 and 1.0. D. 2.0. E. Can t say without knowing Q H. 2013 Pearson Education,
More informationTHERMODYNAMICS b) If the temperatures of two bodies are equal then they are said to be in thermal equilibrium.
THERMODYNAMICS Important Points:. Zeroth Law of Thermodynamics: a) This law gives the concept of temperature. b) If the temperatures of two bodies are equal then they are said to be in thermal equilibrium.
More informationTwo mark questions and answers UNIT II SECOND LAW 1. Define Clausius statement. It is impossible for a self-acting machine working in a cyclic process, to transfer heat from a body at lower temperature
More informationVersion 001 HW 15 Thermodynamics C&J sizemore (21301jtsizemore) 1
Version 001 HW 15 Thermodynamics C&J sizemore 21301jtsizemore 1 This print-out should have 38 questions. Multiple-choice questions may continue on the next column or page find all choices before answering.
More informationSurvey of Thermodynamic Processes and First and Second Laws
Survey of Thermodynamic Processes and First and Second Laws Please select only one of the five choices, (a)-(e) for each of the 33 questions. All temperatures T are absolute temperatures. All experiments
More informationChapter 11 Heat Engines and The Second Law of Thermodynamics
Chapter 11 Heat Engines and The Second Law of Thermodynamics Heat Engines Heat engines use a temperature difference involving a high temperature (T H ) and a low temperature (T C ) to do mechanical work.
More informationDistinguish between an isothermal process and an adiabatic process as applied to an ideal gas (2)
1. This question is about thermodynamic processes. (a) Distinguish between an isothermal process and an adiabatic process as applied to an ideal gas.......... An ideal gas is held in a container by a moveable
More informationPhysics 101: Lecture 28 Thermodynamics II
Physics 101: Lecture 28 Thermodynamics II Final Today s lecture will cover Textbook Chapter 15.6-15.9 Check Final Exam Room Assignment! Bring ID! Be sure to check your gradebook! (send me your net ID if
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
CH. 19 PRACTICE Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) When a fixed amount of ideal gas goes through an isobaric expansion, A) its
More information1. Second Law of Thermodynamics
1. Second Law of hermodynamics he first law describes how the state of a system changes in response to work it performs and heat absorbed. he second law deals with direction of thermodynamic processes
More informationIrreversible Processes
Lecture 15 Heat Engines Review & Examples p p b b Hot reservoir at T h p a a c adiabats Heat leak Heat pump Q h Q c W d V 1 V 2 V Cold reservoir at T c Lecture 15, p 1 Irreversible Processes Entropy-increasing
More informationChapter 4 - Second Law of Thermodynamics
Chapter 4 - The motive power of heat is independent of the agents employed to realize it. -Nicolas Léonard Sadi Carnot David J. Starling Penn State Hazleton Fall 2013 An irreversible process is a process
More informationThermodynamic system is classified into the following three systems. (ii) Closed System It exchanges only energy (not matter) with surroundings.
1 P a g e The branch of physics which deals with the study of transformation of heat energy into other forms of energy and vice-versa. A thermodynamical system is said to be in thermal equilibrium when
More informationS = S(f) S(i) dq rev /T. ds = dq rev /T
In 1855, Clausius proved the following (it is actually a corollary to Clausius Theorem ): If a system changes between two equilibrium states, i and f, the integral dq rev /T is the same for any reversible
More informationTHERMODYNAMICS. Zeroth law of thermodynamics. Isotherm
12 THERMODYNAMICS Zeroth law of thermodynamics Two systems separately in thermal equilibrium with a third system are in thermal equilibrium with each other. Isotherm It is the graph connecting pressure
More informationThermodynamics: The Laws
Thermodynamics: The Laws Resources: Serway The Laws of Thermodynamics: 12 AP Physics B Videos Physics B Lesson 29: Laws of Thermodynamics Thermodynamics Thermodynamics is the study of heat and thermal
More informationCHAPTER - 12 THERMODYNAMICS
CHAPER - HERMODYNAMICS ONE MARK QUESIONS. What is hermodynamics?. Mention the Macroscopic variables to specify the thermodynamics. 3. How does thermodynamics differ from Mechanics? 4. What is thermodynamic
More informationTHE SECOND LAW OF THERMODYNAMICS. Professor Benjamin G. Levine CEM 182H Lecture 5
THE SECOND LAW OF THERMODYNAMICS Professor Benjamin G. Levine CEM 182H Lecture 5 Chemical Equilibrium N 2 + 3 H 2 2 NH 3 Chemical reactions go in both directions Systems started from any initial state
More informationPhysics 121, April 29, The Second Law of Thermodynamics.
Physics 121, April 29, 2008. The Second Law of Thermodynamics. http://www.horizons.uc.edu/masterjuly1998/oncampus.htm Physics 121. April 29, 2008. Course Information Topics to be discussed today: The Second
More informationLesson 12. Luis Anchordoqui. Physics 168. Tuesday, November 28, 17
Lesson 12 Physics 168 1 Temperature and Kinetic Theory of Gases 2 Atomic Theory of Matter On microscopic scale, arrangements of molecules in solids, liquids, and gases are quite different 3 Temperature
More informationDownloaded from
Chapter 12 (Thermodynamics) Multiple Choice Questions Single Correct Answer Type Q1. An ideal gas undergoes four different processes from the same initial state (figure). Four processes are adiabatic,
More informationCHEM Thermodynamics. Work. There are two ways to change the internal energy of a system:
There are two ways to change the internal energy of a system: Thermodynamics Work 1. By flow of heat, q Heat is the transfer of thermal energy between and the surroundings 2. By doing work, w Work can
More informationPhysics 115. Specific heats revisited Entropy. General Physics II. Session 13
Physics 115 General Physics II Session 13 Specific heats revisited Entropy R. J. Wilkes Email: phy115a@u.washington.edu Home page: http://courses.washington.edu/phy115a/ 4/22/14 Physics 115 1 Lecture Schedule
More information18.13 Review & Summary
5/2/10 10:04 PM Print this page 18.13 Review & Summary Temperature; Thermometers Temperature is an SI base quantity related to our sense of hot and cold. It is measured with a thermometer, which contains
More information1. Second Law of Thermodynamics
1. Second Law of hermodynamics he first law describes how the state of a system changes in response to work it performs and heat absorbed. However, the first law cannot explain certain facts about thermal
More informationChapter 10 Temperature and Heat
Chapter 10 Temperature and Heat Thermodynamics deals with 1. Temperature. 2. The transfer and transformation of energy. 3. The relationship between macroscopic properties and microscopic dynamics. Temperature
More informationThermodynamics. AP Physics B
Thermodynamics AP Physics B Important Distinctions Thermodynamics study of processes in which energy is transferred as heat and work. There is a difference between heat and work: Heat is energy transferred
More informationPHY101: Major Concepts in Physics I
Welcome back to PHY101: Major Concepts in Physics I Photo: S. T. Cummins Photo: S. T. Cummins Announcements Today is our final class! We will first discuss more on Chapters 14-15 and then conduct a short
More informationNiraj Sir THERMODYNAMICS
THERMODYNAMICS Thermal Equilibrium:- Two systems are said to be in thermal equilibrium with each other if they have the same temperature. Thermo dynamical system:- An assembly of large numbers of particles
More informationSPONTANEOUS PROCESSES AND THERMODYNAMIC EQUILIBRIUM
13 CHAPER SPONANEOUS PROCESSES AND HERMODYNAMIC EQUILIBRIUM 13.1 he Nature of Spontaneous Processes 13.2 Entropy and Spontaneity: A Molecular Statistical Interpretation 13.3 Entropy and Heat: Macroscopic
More informationTHERMODINAMICS. Tóth Mónika
THERMODINAMICS Tóth Mónika 2014 monika.a.toth@aok.pte.hu Temperature Temperature: is related to the average energy of the motion of the particles of an object or system. Different temperature scales. Thermometer
More informationThermodynamic Third class Dr. Arkan J. Hadi
5.5 ENTROPY CHANGES OF AN IDEAL GAS For one mole or a unit mass of fluid undergoing a mechanically reversible process in a closed system, the first law, Eq. (2.8), becomes: Differentiation of the defining
More informationSolutions. The cabin heat is lost by conduction through the walls. dq/dt = -KA/L ΔT = -A/R ΔT = -200 m 2 / 1.0 m 2 C /W 40 C = W
Department of Physics University of California, Berkeley Physics 7b Section 2 Spring semester 2007 Mid-term examination 1 Tuesday Feb. 20, 6:00 8:00 PM Solutions 1) (15 points) A cabin in the sierra mountains
More informationPhysics 207 Lecture 27. Lecture 26. Chapters 18, entropy and second law of thermodynamics Chapter 19, heat engines and refrigerators
Goals: Lecture 26 Chapters 18, entropy and second law of thermodynamics Chapter 19, heat engines and refrigerators Reading assignment for Wednesday: Chapter 20. Physics 207: Lecture 27, Pg 1 Entropy A
More informationCHAPTER 15 The Laws of Thermodynamics. Units
CHAPTER 15 The Laws of Thermodynamics Units The First Law of Thermodynamics Thermodynamic Processes and the First Law Human Metabolism and the First Law The Second Law of Thermodynamics Introduction Heat
More informationModule - 1: Thermodynamics
Thermodynamics: Module - : Thermodynamics Thermodynamics (Greek: thermos = heat and dynamic = change) is the study of the conversion of energy between heat and other forms, mechanical in particular. All
More informationIrreversible Processes
Irreversible Processes Examples: Block sliding on table comes to rest due to friction: KE converted to heat. Heat flows from hot object to cold object. Air flows into an evacuated chamber. Reverse process
More informationMME 2010 METALLURGICAL THERMODYNAMICS II. Fundamentals of Thermodynamics for Systems of Constant Composition
MME 2010 METALLURGICAL THERMODYNAMICS II Fundamentals of Thermodynamics for Systems of Constant Composition Thermodynamics addresses two types of problems: 1- Computation of energy difference between two
More informationIrreversible Processes
Lecture 15 Heat Engines Review & Examples p p b b Hot reservoir at T h p a a c adiabats Heat leak Heat pump Q h Q c W d V 1 V 2 V Cold reservoir at T c Lecture 15, p 1 Irreversible Processes Entropy-increasing
More informationChapter 19 The First Law of Thermodynamics
Chapter 19 The First Law of Thermodynamics The first law of thermodynamics is an extension of the principle of conservation of energy. It includes the transfer of both mechanical and thermal energy. First
More informationReading Assignment #13 :Ch.23: (23-3,5,6,7,8), Ch24: (24-1,2,4,5,6) )] = 450J. ) ( 3x10 5 Pa) ( 1x10 3 m 3
Ph70A Spring 004 Prof. Pui Lam SOLUTION Reading Assignment #3 :h.3: (3-3,5,6,7,8), h4: (4-,,4,5,6) Homework #3: First Law and Second of Thermodynamics Due: Monday 5/3/004.. A monatomic ideal gas is allowed
More informationLecture 10: Heat Engines and Reversible Processes
Lecture 10: Heat Engines and Reversible Processes Last time we started discussing cyclic heat engines these are devices that convert heat energy into mechanical work We found that in general, heat engines
More informationRevision Guide for Chapter 13
Matter: very simple Revision Guide for Chapter Contents Student s Checklist Revision Notes Ideal gas... Ideal gas laws... Assumptions of kinetic theory of gases... 5 Internal energy... 6 Specific thermal
More informationOctober 18, 2011 Carnot cycle - 1
Carnot Cycle In 1824, Sadi Carnot (1796-1832) published a short book, eflections on the Motive Power of Fire (The book is now free online You should try it out) To construct an engine, Carnot noted, at
More informationFree expansion (Joule); Constant U Forced expansion (Joule-Kelvin); Constant H. Joule-Kelvin coefficient - heating or cooling on JK expansion?
...Thermodynamics Adiabats: How c P and c V get into the exponent PV γ Free expansion (Joule); Constant U Forced expansion (Joule-Kelvin); Constant H Joule-Kelvin coefficient - heating or cooling on JK
More informationClassification following properties of the system in Intensive and Extensive
Unit I Classification following properties of the system in Intensive and Extensive Extensive : mass, weight, volume, potential energy, Kinetic energy, Internal energy, entropy, exergy, energy, magnetization
More informationPhysics Fall Mechanics, Thermodynamics, Waves, Fluids. Lecture 32: Heat and Work II. Slide 32-1
Physics 1501 Fall 2008 Mechanics, Thermodynamics, Waves, Fluids Lecture 32: Heat and Work II Slide 32-1 Recap: the first law of thermodynamics Two ways to raise temperature: Thermally: flow of heat Energy
More informationClassical Physics I. PHY131 Lecture 36 Entropy and the Second Law of Thermodynamics. Lecture 36 1
Classical Physics I PHY131 Lecture 36 Entropy and the Second Law of Thermodynamics Lecture 36 1 Recap: (Ir)reversible( Processes Reversible processes are processes that occur under quasi-equilibrium conditions:
More informationChapter 16 The Second Law of Thermodynamics
Chapter 16 The Second Law of Thermodynamics To examine the directions of thermodynamic processes. To study heat engines. To understand internal combustion engines and refrigerators. To learn and apply
More informationLecture 25 Goals: Chapter 18 Understand the molecular basis for pressure and the idealgas
Lecture 5 Goals: Chapter 18 Understand the molecular basis for pressure and the idealgas law. redict the molar specific heats of gases and solids. Understand how heat is transferred via molecular collisions
More informationReversible Processes. Furthermore, there must be no friction (i.e. mechanical energy loss) or turbulence i.e. it must be infinitely slow.
Reversible Processes A reversible thermodynamic process is one in which the universe (i.e. the system and its surroundings) can be returned to their initial conditions. Because heat only flows spontaneously
More informationCHEM 305 Solutions for assignment #4
CEM 05 Solutions for assignment #4 5. A heat engine based on a Carnot cycle does.50 kj of work per cycle and has an efficiency of 45.0%. What are q and q C for one cycle? Since the engine does work on
More informationPhase Changes and Latent Heat
Review Questions Why can a person remove a piece of dry aluminum foil from a hot oven with bare fingers without getting burned, yet will be burned doing so if the foil is wet. Equal quantities of alcohol
More informationSecond Law of Thermodynamics -
Second Law of Thermodynamics - REVIEW ENTROPY EXAMPLE Dr. Garrick 1/19/09 First Law of Thermodynamics you can t win! First Law of Thermodynamics: Energy cannot be Created or Destroyed the total energy
More informationPhys 22: Homework 10 Solutions W A = 5W B Q IN QIN B QOUT A = 2Q OUT 2 QOUT B QIN B A = 3Q IN = QIN B QOUT. e A = W A e B W B A Q IN.
HRK 26.7 Summarizing the information given in the question One way of doing this is as follows. W A = 5W Q IN A = Q IN Q OU A = 2Q OU Use e A = W A Q IN = QIN A QOU Q IN A A A and e = W Q IN = QIN QOU
More informationPhysics 101: Lecture 28 Thermodynamics II
Physics 101: Lecture 28 Thermodynamics II Final Today s lecture will cover Textbook Chapter 15.6-15.9 Check Final Exam Room Assignment! Bring ID! Be sure to check your gradebook! Physics 101: Lecture 28,
More informationCARNOT CYCLE = T = S ( U,V )
hermodynamics CANO CYCE Do not trouble students with history In 1824, Sadi Carnot (1796-1832) published a short book, eflections on the Motive Power of Fire (he book is now free online You should try it
More informationPhysical Biochemistry. Kwan Hee Lee, Ph.D. Handong Global University
Physical Biochemistry Kwan Hee Lee, Ph.D. Handong Global University Week 3 CHAPTER 2 The Second Law: Entropy of the Universe increases What is entropy Definition: measure of disorder The greater the disorder,
More information