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MS212 Thermodynamics of Materials (소재열역학의이해)
Lecture Note: Course Intro + Chapter 1
Byungha Shin (신병하)Dept. of MSE, KAIST
1
2017 Spring Semester
Course Information
Teaching StaffProf. Byungha Shin (Teacher)byungha@kaist.ac.kr, X 3315, W1-1 #3404 office hours: 16:00 – 17:30 on Tue and Thurs or by appointment
Mr. Giuk Jeong (Teaching Assistant)zeuskhan@kaist.ac.kr, X 3355, W1-1 #2432
Mr. Joon Yun Kim (Teaching Assistant)wnsdus@kaist.ac.kr, X 3355, W1-1 #2432
Meeting time and placeTime: 1:00 – 2:15 on Tues and ThursLocation: E11 Creative Learning Bldg (창의학습관) #303
Textbook Gaskel, “Introduction to the Thermodynamics of Materials”, 5th Ed.
Course Information
Course InformationSyllabus
Chap 1. Introduction and Definition of Terms (1 lecture)Chap 2. The First Law of Thermodynamics (1.5 lectures)Chap 3. The Second Law of Thermodynamics (3 lectures)Chap 4. The Statistical Interpretation of Entropy (2 lectures)Chap 5. Auxiliary Functions (2.5 lectures)Chap 6. Heat Capacity, Enthalpy, Entropy and the Third
Law of Thermodynamics (3 lectures)Chap 7. Phase Equilibrium in a One-Component System (3 lectures)Chap 8. The Behavior of Gases (3 lectures)Chap 9. The Behavior of Solutions (3 lectures)Chap 10. Gibbs Free Energy Composition and Phase Diagram (3 lectures)
Course Information• No class on:
4/18 (Tues) & 4/20 (Thurs): Mid-term exam period5/18 (Thurs): K-MRS spring meeting5/23 (Tues) & 5/25 (Thurs): E-MRS spring meeting6/5 (Tues): Memorial Day6/13 (Tues) & 6/15 (Thurs): Final exam period
• 2-3 Make-up classes will be scheduled: Saturday afternoon
• Discussion sessions- to review and discuss materials covered in regular classes prior to
each session (mostly answering students’ questions)- it will be helpful if students prepare a list of questions and send it to
Prof. Shin well ahead of each session- will be scheduled once every 2-3 weeks (Saturday afternoon; exact
dates to be determined)?- in Korean language
Course Schedule
GradingWeekly homework (total 8) 20%Mid-term exam 1 25%Mid-term exam 2 25%Final Exam 30%Bonus points for class participation + α
Exam Dates and TimeMid-term exam 1: 3/30 (Thurs), 12:30 pm – 2:30 pm or in the eveningMid-term exam 2: 5/11 (Thurs), 12:30 pm – 2:30 pm or in the eveningFinal exam: 6/13 (Tues), 1:00 pm – 4:00 pm or in the evening(extra time will be given to those who want it)
Coverage of ExamExams are open-book and open-note, but no internet and no smartphone.Mid-term exam 1: Chaps. 1 – 4Mid-term exam 1: Chaps. 5 – 7Mid-term exam 1: Chaps. 1 – 10
Grading
Course InformationHow to succeed in MS 212?
• What counts in MS212 is understanding the basic concept. Don’t get overwhelmed by formulae and memorization of them is useless (exams are open-note and open-book)
• Regular work, putting in a substantial amount of time each week.
• In preparation for each lecture, please read assigned sections of the textbook. At the end of each lecture, I will assign which sections to read for the next lecture.
• Active class participation.
Course InformationClass Participation
Taken from presentation slides of Prof. Eric Mazur at Harvard University
• Lecture notes will be given to you via email• Make sure email address that you put on
KAIST portal is the one you are actually using.
Announcement
• Lecture notes will be uploaded to KLMS (http://klms.kaist.ac.kr/) prior to each lecture (a notification email will be sent once upload is done).
ThermodynamicsThermodynamics
Greek for “Heat”
Greek for “force”
• Deals with ’heat’ and ‘work’ plus the material properties of substances which bear a relation to heat and work
“… Not knowing the second law of thermodynamics is like never having read Shakespeare” -- C. P. Snow
“ A theory is the more impressive the greater the simplicity of its premises, the more different kind of things it relates, and the more extended is its area of applicability. Therefore, the deep impression which classical thermodynamics made upon me. It is the only physical theory concerning which I am convinced that, within the framework of the applicability of its basic concepts, it will never be overthrown.” -- Albert Einstein
0th law Define Temperature (T)
1st law Define Energy (U)“You can’t win, you can only break even”
2nd law Define Entropy (S)“You can break even only at absolute zero”
3rd law Define absolute value of S“You cannot reach absolute zero”
Conclusion: You can neither win nor break even. You lose!
Laws of Thermodynamics
System:
Surroundings (Environment):
Boundary:
Any collection of matter that is we want to study
The universe outside the system
The interface dividing the system from the surroundings
• Open: Exchange energy and mass
• Close: Exchange energy, but not mass
• Isolated: Do not exchange anything
Definition of Terms
Slide courtesy of Prof. WooChul Jung
• Microscopic propertiesmolecule, position, velocity, mode of motion, etc.e.g. how many parameters to describe 1 mole
of Ar gas?
• Macroscopic properties (variables)temperature, pressure, volume, density, etc.
• Homogeneous or Heterogeneous (in terms of phase)phase : finite volume in which the properties are uniformly constant
• Number of componentscomponent: chemical species of fixed composition
• Equilibrium or non-equilibriumequilibrium: There are no net flows of matter or of energy, no phase change. No change in time and in space
Description of System
Slide courtesy of Prof. WooChul Jung
• Extensive: dependent on the size of the system (V, n, m, etc.)• Intensive: independent on the size of the system (T, P, r, etc.)• You can normalized extensive properties by unit volume, unit
mole, or unit mass of the system.
V: volume of the systemV=V/n: molar volume
C: heat capacityc=C/m: specific heat capacity
_
Macroscopic Properties
• For simple compressible (such as gas) pure (1 component) substance, only two independent macroscopic properties enough to uniquely specify the state of a system that is closed (fixed mass).
?
if two systems are each in thermal equilibrium with a third system, they are also in thermal equilibrium with each other.
0th Law of Thermodynamics
Image obtained from http://www.grc.nasa.gov/WWW/k-12/airplane/thermo0.html
Hot Cold+Heat
= Warm Warm
Slide courtesy of Prof. WooChul Jung
Temperature?
Boyle’s Law (1660): V ∝ 1/P at constant T
Charles’ Law (1787): V ∝ T at constant P
Gay-Lussac’s law (1802): 𝛼𝛼 =1𝑉𝑉0
𝜕𝜕𝑉𝑉𝜕𝜕𝑇𝑇 𝑃𝑃
=1
267
1273.15
now,
• Property that varies with T: Resistivity, volume, color, etc.• Reference points: Boiling point, freezing point, triple point of H2O, etc.
T
PV
100oC
(PV)B
-273.15oC
(PV)F
PV = f(T), a linear fcn of T
• T = -273.15oC: absolute zero• This defines a new temperature
scale (Kelvin).• T(K) = T(oC) + 273.15
• Slope: R (gas constant) = 8.31451 J K-1 mol-1
Slide courtesy of Prof. WooChul Jung
Equation of State of Ideal GasIdeal gas: a theoretical gas composed of a set of randomly moving, non-interacting point particles.
PV = nRT or PV = RT
Unit consideration:Pressure = force / area 1 atm = 101,325 N/m2
Volume = area x distance (height) 1 L = 10-3 m3
1 L∙atm = 101.325 N∙m2 = 101.325 J
_
𝑅𝑅 =𝑃𝑃𝑉𝑉𝑇𝑇
=𝑃𝑃0𝑉𝑉0𝑇𝑇0
=(1 atm)(22.41 𝐿𝐿)
273.15 𝐾𝐾 = 0.08205 L∙atm / (mol∙K)= 8.314 J / (mol∙K)= 1.987 cal / (mol∙K)
How to describe going from one equilibrium state to the other?
EquilibriumState A
EquilibriumState B
- Macroscopic variables(TA, PA, VA, etc.)
- Phase (homo/hetero)- # of component
- Macroscopic variables(TB, PB, VB, etc.)
- Phase (homo/hetero)- # of component
>
>
State Function
Slide courtesy of Prof. WooChul Jung
How fast is determined by kinetics, not by thermodynamics
Path from one state to another• Adiabatic: no heat transfer with surroundings• Isobaric: constant pressure• Isothermal: constant temperature• Isochoric: constant volume• Isentropic: constant entropy • etc.
EquilibriumState A
(TA & PA)
EquilibriumState B
(TB & PB)
T
P
TA TB
PB
PA IsobaricTA TB
IsothermalPA PB
State Function
Slide courtesy of Prof. WooChul Jung
V = V(T,P): Already existing property like Gyeryong Mt. State function
T
P
V
T1
T2
P1 P2
1
2
State Function
𝑑𝑑𝑉𝑉 =𝜕𝜕𝑉𝑉𝜕𝜕𝑇𝑇 𝑃𝑃1
𝑑𝑑𝑇𝑇 +𝜕𝜕𝑉𝑉𝜕𝜕𝑃𝑃 𝑇𝑇2
𝑑𝑑𝑃𝑃
=𝜕𝜕𝑉𝑉𝜕𝜕𝑃𝑃 𝑇𝑇1
𝑑𝑑𝑃𝑃 +𝜕𝜕𝑉𝑉𝜕𝜕𝑇𝑇 𝑃𝑃2
𝑑𝑑𝑇𝑇
�𝑉𝑉1
𝑉𝑉2𝑑𝑑𝑉𝑉 = �
𝑇𝑇1
𝑇𝑇2 𝜕𝜕𝑉𝑉𝜕𝜕𝑇𝑇 𝑃𝑃1
𝑑𝑑𝑇𝑇 + �𝑃𝑃1
𝑃𝑃2 𝜕𝜕𝑉𝑉𝜕𝜕𝑃𝑃 𝑇𝑇2
𝑑𝑑𝑃𝑃
= �𝑃𝑃1
𝑃𝑃2 𝜕𝜕𝑉𝑉𝜕𝜕𝑃𝑃 𝑇𝑇1
𝑑𝑑𝑃𝑃 + �𝑇𝑇1
𝑇𝑇2 𝜕𝜕𝑉𝑉𝜕𝜕𝑇𝑇 𝑃𝑃2
𝑑𝑑𝑇𝑇
= 𝑉𝑉2 − 𝑉𝑉1
�𝑑𝑑𝑉𝑉 = 0 : path-independentdV: exact differential State function
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