EMA 5106 Thermodynamics for Materials Science
INSTRUCTOR:
Dr. Jiyu Fang
Office:
ENGR-I, ROOM 207B
E-mail:
Jfang@mail.ucf.edu
Office hours:
M/W 10:00am-11:00am
OBJECTIVES:
To enable students to understand and apply the
concepts and principles of thermodyna

Regular solution
G M RT ( X A ln X A X B ln X B )
H
M
X A H
M
A
X BH
M
B
' ( X A X B2 X B X A2 ) ' X A X B
Raoult ideal solution
G M ,id RT ( X A ln X A X B ln X B )
H M ,id 0
The properties of a regular solution are best examined by the
concept of e

Chapter 9: The Behavior of Solution (Continue)
Partial molar Gibbs free energy of i in the solution: Change in Gibbs
free energy by mixing one mole of component i to the solution
G i (l ) G RT ln pi
o
i
Partial molar Gibbs free energy of the solution of

Partial molar quantities
The molar value of any property of a component of a mixture is
called the partial molar value of the property
A mixture with component i and j
The partial molar value of property Q
of component i in a mixture
Q
Qi ( )T , P ,n j
n

For a reversible Carnot engine
Efficiency:
Heat reservoir t2
q2
w
Carnot
q1
Cold reservoir t1
w
q2
VB
V
V
V
RT1 ln D RT2 ln B RT1 ln B
VA
VC
VA
VA
V
V
RT2 ln B
RT2 ln B
VA
VA
RT2 ln
R(T2 T1 )ln
RT2 ln
VB
VA
VB
VA
T2 T1
T
1 1
T2
T2
For a Carnot Cycle proc

Heat engine
Convert some heat to work
Heat reservoir at
high temperature T2
q2
withdrawn
Heat
engine
q1
transferred
Cold reservoir at
low temperature T1
converted
Work, w
After a Carnot Cycle process: the system returns to its initial state
q2
P
t2
A
q2

Einstein Theory-calculation of heat
capacity of a solid as a function of T
Consider a crystal containing n atoms;
each behaves as a harmonic oscillator
which vibrates with a fixed frequency
Einstein crystal
A harmonic oscillator can have the ith
energ

Chapter 3: The Second Law of Thermodynamics
The first law of thermodynamics: energy conservation
State 1
U q w
State 2
Two extreme cases:
Heat Work
q = 0: U = -w
w = 0: U = q
Question:
If q 0 and w 0, is there a definite amount of work, which
the system

Chapter 4: The Statistical Interpretation of Entropy
Classical Thermodynamics - deal with macroscopic, measurable
properties of a system. But it gives little insight about the properties of
atoms and molecules in the system.
Entropy:
For adiabatic system,

The chemical potential
If the composition changes, Gibbs free energy is not only the function of T
and P, but also the function of chemical species (n-number of moles)
G G(T , P, ni , n j , .)
Differentiation of G:
dG (
dG
dG
dG
dG
) P ,ni ,n j . dT ( )T

Chapter 2: The First Law of Thermodynamics
Energy of a system
Kinetic energy: When a system is in motion, it has kinetic energy.
Many forms of kinetic energy
Vibration (the energy due to vibrational motion)
Rotation (the energy due to rotational motion

Chapter 5: Helmholtz free energy A
Since the relationships among the thermodynamic properties of a system
determine the equilibrium in the system, it is important to establish these
relationships
Combining the 1st and the 2nd law
dU q w
dS
q
w PdV
T
dU T

Effect of temperature on entropy if temperature is higher than melting
temperature
A(S,0)
A(l,T)
A(S,Tm)
Tm
c p(S )
298
T
ST S 298
A(l,Tm)
T
cl ( S )
Tm
T
dT S m
Richards rule: the entropy of the fusion
of metals should have the same value,
leading to a

Chapter 8: The Behavior of Gases
P-V-T relationship of gases
- Ideal gas
PV
1
RT
PV
1limitP0
- Real gas: Experimental observation
RT
When P approaches to 0, gas behaved as ideal gas.
P-V curves
(isothermal lines) for
real gas at different T
- Deceasing

The Behavior of Gases
P-V-T relationship of gases
There is a critical temperature
At critical Tcr
T < Tcr
Liquid and vapor can exist
T > Tcr
No liquid phase
For a closed system of fixed composition at constant temperature, the change in
Gibbs free energy

EML 3101
Thermodynamics of Mechanical Systems
Spring 2016
Test 4
April 1,‘ 2016
50 minutes
Open Textbook
Do both problems (10 points each)
1. One kmol of hydrogen molecules is burned completely with 50% excess air in a steady-flow
combustion process. (3)

EML 3101
Thermodynamics of Mechanical Systems
Spring 2016
Test 5
April 13, 2016
50 minutes
Open Textbook. No notes allowed except for one page of formulae on one side of an 8.5” x 11”
piece of paper.
An adiabatic turbine is supplied with steam at 12.5 MPa

Chapter 12: Reaction involving pure condensed phases and
gaseous phase
1
M ( s ) O2 MO( s )
(1)
2
M (g)
1
O2 MO( g )
2
(2)
Equilibrium:
pM and pMO are saturated pressures of M and MO
Gas reaction is equilibrium
For reaction (2):
p MO
G o
KP
exp(
)
1

Review
System: A matter, or a region in space
Surroundings (environments): The region outside the system.
Boundary: The surface that separates the system from its
surroundings.
System
Boundary
Surroundings
Open System: Both mass and energy can cross the b

Standard Gibbs free energy change
1
Reaction: H 2 O2 H 2O
2
G o 247,500 55.85T
If PO2=10-10 atm, T = 2000K
At T = 2000K
Equilibrium constant:
G o
K p exp(
)
RT
KP
247,500 55.85
3
K P exp(
) 3.521 10
8.314T 8.314
pH O
2
1/ 2
O2
pH p
2
the state of equili

Gibbs free energy of formation of a solution:
G ' n A G A nB G B
a binary A-B system
Partial molar value G for A and B
Molar Gibbs free energy of the solution
G X AGA X BGB
dG
GA G XB
dX A
dG
GB G X A
dX B
XB
nB
n A nB
nA
XA
n A nB
These expressions re

Chapter 10: Gibbs Free Energy - Composition
Phase Diagram of Binary Systems (Continue)
The influence of T on the activity of B with composition. The
activity was obtained from the intercepts with the XB = 1 axis, of
M
tangent drawn to the free energy curv

Chapter 10: Gibbs Free Energy, Composition, and
Phase Diagram of Binary Systems
Phases:
Gas
Liquid
Solid
Phase diagram:
Phase diagram the stability of phases as
a function of temperature and composition.
Stable phases:
Lowest Gibbs free energy
Coexist

Chapter 9: The Behavior of Solution
Solution
Strong interactions between atoms/molecules
The interactions are determined by atom/molecule size and
electro-negativity.
The interactions determine how extent a component is soluble
in a solution and whethe

Problem 1. The Vapor pressure of solid NaF varies with temperature as
34450
ln p
2.01ln T 33.73
T
The Vapor pressure of liquid NaF varies with temperature
as
ln p
31090
2.52ln T 34.66
T
Calculate
1.The normal boiling temperature of NaF
2.The temperatu

EML 3101 Thermodynamics of Mechanical Systems
Fall 20 14
Exam 1 (Make up)
October 7, 2014
60 minutes
Open Textbook
Do both problems
1. An adiabatic steam turbine shown below receives 30 kg of steam per second at 3 MPa,
350°C. At the point in the turbine w