VIII. Entropy for a reversible process at constant T dQ is path dependent dS is path independent S is function of state S is additive function for any.

Slides:

Advertisements

Similar presentations

Physics 2 Chapter 20 problems Prepared by Vince Zaccone

Advertisements

Chapter 12 The Laws of Thermodynamics. Work in a Gas Cylinder.

Kinetic Theory and Thermodynamics

ConcepTest Clicker Questions

Advanced Thermodynamics Note 4 The Second Law of Thermodynamics

Entropy and the Second Law of Thermodynamics

Second Law of Thermodynamics Physics 202 Professor Lee Carkner Lecture 18.

Fig Water molecules are arranged in a regular ordered way in an ice crystal.

Physics 52 - Heat and Optics Dr. Joseph F. Becker Physics Department San Jose State University © 2003 J. F. Becker.

Results of Midterm points # of students GradePoints A B+B B46-55 C+C C26-40 D,F

PHY PHYSICS 231 Lecture 32: Entropy Remco Zegers Question hours: Thursday 12:00-13:00 & 17:15-18:15 Helproom “Another way of stating the Second Law.

For the cyclic process shown, W is:D A] 0, because it’s a loop B] p 0 V 0 C] - p 0 V 0 D] 2 p 0 V 0 E] 6 p 0 V 0 For the cyclic process shown,  U is:

Thermo – the 2 nd Law Two factors effect any process such as a chemical reaction. 1.the difference in any energy term, ΔE, ΔH or ΔS, between the reactants.

MHS Physics Department AP Unit II C 2 Laws of Thermodynamics Ref: Chapter 12.

Chapter 15 Thermodynamics. MFMcGrawChap15d-Thermo-Revised 5/5/102 Chapter 15: Thermodynamics The first law of thermodynamics Thermodynamic processes Thermodynamic.

Thermodynamics AP Physics 2.

Thermodynamics. Terms used frequently in thermodynamics System Surroundings Isolated system Closed system Open system State of a system State variables.

Topic 10 Sections 2 and 3.  Statement Number Assessment Statement Deduce an expression for the work involved in a volume change of a gas at constant.

17.4 State Variables State variables describe the state of a system

Spontaneity of Chemical and Physical Processes: The Second and Third Laws of Thermodynamics 1.

Q19. Second Law of Thermodynamics

The Second Law of Thermodynamics

The Laws of Thermodynamics

Worksheet A thermodynamic system undergoes a three-step process. An adiabatic expansion takes it from state 1 to state 2; heat is added at constant pressure.

Entropy Change (at Constant Volume)

ERT 108 Physical Chemistry The Second Law of Thermodynamics by Miss Anis Atikah binti Ahmad

© 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the use of instructors in teaching their.

Thermodynamics Chapter 12.

Lecture Outline Chapter 12 College Physics, 7 th Edition Wilson / Buffa / Lou © 2010 Pearson Education, Inc.

An adiabatic free expansion of a gas in a thermally isolated container is not reversible because _____ . Select the correct answer. work must be.

© 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the use of instructors in teaching their.

when system is subdivided? Intensive variables: T, P Extensive variables: V, E, H, heat capacity C.

The Second Law of Thermodynamics

Chapter 20 Entropy and the Second Law of Thermodynamics 20.1 Some one-way processes Which is closer to ‘common’ sense? Ink diffusing in a beaker of water.

26.1 Entropy Changes in the Surroundings Now that we have seen how to calculate  S system for reversible and irreversible processes, the relation:  S.

Entropy Changes in Irreversible Processes The efficiency of an irreversible Carnot cycle is always less than the efficiency of a reversible Carnot cycle.

Chapter 13: Thermodynamics

MME 2009 Metallurgical Thermodynamics

Chemical Equilibrium By Doba Jackson, Ph.D.. Outline of Chpt 5 Gibbs Energy and Helmholtz Energy Gibbs energy of a reaction mixture (Chemical Potential)

Thermodynamics Internal energy of a system can be increased either by adding energy to the system or by doing work on the system Remember internal energy.

Constant volume (isochoric) process No work is done by the gas: W = 0. The P-V diagram is a vertical line, going up if heat is added, and going down if.

IV. Kinetic theory (continued – see previous lecture) 5. Heat capacitance a) Monoatomic gas } b) Equipartition principle. Degrees of freedom Diatomic gas,

Physics 1210/1310 Mechanics&Thermodynamics Lecture 39~40 Thermodynamics.

Reversible and irreversible processes Physics Entropy 28 September 2011.

Physics 207: Lecture 29, Pg 1 Physics 207, Lecture 29, Dec. 13 l Agenda: Finish Ch. 22, Start review, Evaluations  Heat engines and Second Law of thermodynamics.

203/4c18:1 Chapter 18: The Second Law of Thermodynamics Directions of a thermodynamic process Reversible processes: Thermodynamic processes which can be.

ERT 108/3 PHYSICAL CHEMISTRY SECOND LAW OF THERMODYNAMICS Prepared by: Pn. Hairul Nazirah Abdul Halim.

Physics 101 Lecture 11. Thermal Physics Thermodynamics.

Advanced Placement Physics B Chapter 12: Heat Engines and Efficiency.

Work in Thermodynamic Processes

THE SECOND LAW OF THERMODYNAMICS Entropy. Entropy and the direction of time Microscopically the eqs. of physics are time reversible ie you can turn the.

SUBJECT : Engineering Thermodynamics. UNIT : Entropy Prepared by NAMEENROLLMENT NO SUNILKUMAR PATEL UTSAVKUMAR PATEL VAIDIK PATEL

Lecture Outline Chapter 12 College Physics, 7 th Edition Wilson / Buffa / Lou © 2010 Pearson Education, Inc.

1 12. Thermodynamics The essential concepts here are heat and temperature. Heat is a form of energy transferred between a system and an environment due.

Chapter 20 Lecture 35: Entropy and the Second Law of Thermodynamics HW13 (problems):19.3, 19.10, 19.44, 19.75, 20.5, 20.18, 20.28,

Learning Goals for Chapter 20 Looking forward at … the difference between reversible and irreversible processes. the physics of internal-combustion engines.

The Second Law of Thermodynamics

ERT 108 Physical Chemistry

Which statement about these two thermodynamic processes is correct?

The Laws of Thermodynamics

Entropy and the Second Law of Thermodynamics

Mechanics & Thermodynamics

Q20.1 Metal box at 0°C Metal box at 0°C

The Second Law of Thermodynamics

Some processes that do not occur are not in violation of the First Law

Change in Entropy Entropy as a State Function

Entropy and the Second Law of Thermodynamics

Second Law of Thermodynamics

Thermodynamics is the science that bind heat with energy and work.

Presentation transcript:

VIII. Entropy for a reversible process at constant T dQ is path dependent dS is path independent S is function of state S is additive function for any process (including irreversible) For closed, isolated system (dQ = 0): 2.The second law of thermodynamics any reversible cycle: ΔS=0 any irreversible process in closed isolated system: ΔS>0 1. Macroscopic definition of entropy

Example 1: This P-V diagram represents a system consisting of a fixed amount of ideal gas that undergoes three different processes in going from state A to state B. Rank the change in entropy of the system for each process. V State A I P State B 2 3 ΔS 1 = ΔS 2 = ΔS 3 = S B - S A The same as: ΔT 1 = ΔT 2 = ΔT 3 = T B - T A ΔU 1 = ΔU 2 = ΔU 3 = U B - U A Example 2: Which of the following statements is false? A. The change of entropy in a cyclic process is zero B. The change of entropy for any adiabatic process is zero C. The change of entropy for any isothermal process is zero D. Entropy for a closed, isolated system is constant E. Entropy of a system can decrease

Example 3: 50.0 kg of water is converted to ice at 0.0ºC. What is the change in entropy of water? m = 85.0 kg T = 0.0ºC L = 334*10 3 J/kg ΔS - ? Example 4: The isolated system is 50.0 kg of ice at 0 ˚C plus the temperature reservoir at slightly above 0 ˚C that is used to melt the ice. What is the change in entropy of the system when the ice is melted ? Solution: The system is isolated: Q ice = -Q reservoir The ice and the reservoir are at almost the same temperature: T ic = T reservoir =T The system consists of both the ice and the temperature reservoir: ΔS = 0. Therefore the process is reversible!

3. Entropy of ideal gas

3a. Free expansion of ideal gas A given amount of an ideal gas undergo free expansion from volumeV 1 to V 2 Gas forms a closed and thermally isolated system. Because of that: W=0, Q=0ΔU=0 ΔT=0 T 1 = T 2 General equation for the entropy change of any ideal gas: Closed and thermally isolated system with ΔS>0: the process is irreversible! Example: Two moles of an ideal gas undergo an adiabatic free expansion from V 1 = 1.00 L to V 2 = e1.00 L = 2.72 L. (The gas is an isolated system). The change in the entropy of the gas is __ J/K. The process is irreversible!

3b. Reversible isothermal expansion of ideal gas

3c. Reversible Adiabatic Expansion of Ideal Gas

4. Microscopic interpretation of entropy number of possible microscopic states Example 6: A thermally insulated box is divided by a partition into to compartments, each having volume V. Initially one compartment contains n moles of an ideal gas at temperature T, and other compartment is evacuated. We then break the partition, and gas expands to fill both compartments. What is the entropy change in this free- expansion process?