Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 8, due 3/25
Problem 1 (25 pts)
S
?
T P
Find Cp for any substance in terms of V, T, P and S. Hint: How is Cp related to
Problem 2 (25 pts)
For a substance described by the van der Waals equation of state with a constant heat capacity
Cv:
(a)
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 7, due 3/18
Problem 1 (25 pts).
A 5 kg bar of gold is taken out of a furnace at 500 oC and allowed to cool in air at ambient
conditions (25 oC, 1 bar). The room where the gold cools is very, very large. What is the
change of entropy of the univer
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 10, due 4/15
Problem 1 (25 pts)
If a gas can be described by the Clausius equation of state:
Where b is a constant, then:
(a) Obtain an expression for the residual volume (5 pts)
(b) Obtain an expression for the residual enthalpy (5 pts)
(c) Obta
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 12, due 4/29
Problem 1. (10 pts)
Fill out the SRTEs for this course on ANGEL. Did you fill them out (yes/no)?
Problem 2. (20 pts)
A stream of propane is throttled from 4.298 bar and 450 K to 0.22 bar. This process is irreversible due to
frictiona
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 11, due 4/22
Problem 1 (25 pts)
Using the following vapor pressure data for water and ice:
Psat (mm Hg)
T (oC)
Ice
4
3.280
Ice
2
3.880
Water
2
5.294
Water
4
6.101
Estimate the following:
a.
b.
c.
d.
Heat of sublimation of ice (10 pts)
Heat of v
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Homework 9, due 4/8
Problem 1 (25 pts)
If a substance can be described by the van der Waals equation of state with a constant heat capacity
CV:
a. Find the change in internal energy U if the temperature and volume go from T0, V0 to T,
V. (10 pts)
b. Find
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
Homework 6, due Friday March 4
Problem 1 (25 pts)
a. For a reversible process involving ideal gases in a closed system, show that
S = Cv ln(T2/T1) for a constant volume process
S = Cp ln(T2/T1) for a constant pressure process
S = R ln(V2/V1) = R ln(P1/P2)
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
Homewo
ork 3, due 2/05 at the beginning off class
1. (a) Use
U the steam
m tables to deetermine the phase of waater at the foollowing connditions. Expplain
why you
y made yo
our choice. (10
( pts)
o
i. 25 C, 1 bar
b
iii. 200 oC, 10
0 bar
iiii. 250 oC, 50
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
CD
a) l ) 16:0! (“'0’ ( 3a." “hffir”; 72rd j 6/7,. E7306 6") / )3'7/ )
i f ) gas ( ’i'"77;,; @m 560,; Tm WM? (a go ) gig/J
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j )1!) fr? ":6! ( gqf 6;) £94223; ' L.) ff.) 5:,
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M : 1,61? k7 My SOLE/E. o
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
Homework 5, due 2/26
Based on the feedback I received in class, some changes to the format of the homework
assignments have been made. Answers are now provided for select questions. Also, you
are now asked to sketch or explain whether your answer makes se
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
Homework 1, due Wednesday, January 20h inclass, before the class period begins
Each problem is worth 25 pts. Show your work for full credit. Make sure all numerical answers have the
correct units and the correct number of significant digits.
1. A common
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2016
Homeworrk 2, due Friiday 1/29 at the
t beginning
g of class
List any
a assumptio
ons you need to
t make to so
olve the assignned problemss
a with a pistton and springg arrangemennt on top, as shown in the ffigure
1. Consiider a cylindeer filled with air
b
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2015
Homework Set 3
Due: February 6
Reading: Chapter 2, sections 2.82.12; review of chapter 2.
Problems 2.12., 2.20, 2.24, 2.29 in the textbook.
1
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2014
Homework Set 4
Due: Will not be collected
Reading: Chapter 3; sections 3.13.6
Problems 3.4, 3.5, 3.10, 3.18 in the book.
1
Problem 1 Solution
The work is
Z
W D
V2
P dV
V1
with the integral to be calculated along a path of constant te
Khue Nguyen
HW #2
CH E 220
5/20/2016
Problem 2.3: Use the steam tables to do the following:
a. A drum 3.5 m3 in volume contains steam at 1 bar, 210C. Determine the mass of steam in
the drum.
3.5 3
The specific volume of the drum is: = ()
Using the data fr
Khue Nguyen
CH E 220 HW #3
5/29/16
Problem 3.5:
a) Calculate the amount of work necessary for the reversible expansion of
1 kg of steam from 10 bar to 5 bar. The expansion is to take place in a
cylinder fitted with a weightless piston at the constant temp
Khue Nguyen
CH E 220 #4 HW
06/01/2016
Problem 3.37: At 120 C the saturation pressure of ethanol is 4.3 bar.
a) What is the state of ethanol at 120 C and 10 bar (i.e., compressed liquid, saturated
liquid/vapor, superheated vapor)? At 140 C and 1 bar?
At th
Khue Nguyen
CH E 220
HW #1
05/12/2016
Problem 1.1: The density of liquid ammonia (NH3) at 0 F, 31 psi, is 41.3 lb/ft 3.
a. Calculate the specific volume in ft 3/lb, cm3/g and m3/kg
b. Calculate the molar volume in ft 3/lbmol, cm3/mol and m3/mol
Molecule w
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Problem 1 Solution a) Vapor.
b) The molar mass can be obtained from the relationship between molar volume and density:
D
Mm
V
)
Mm D V
We know density at two pressures, so we need the molar volume in one of them. We choose the lowest
pressure because at 0
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Problem 1 Solution First we write the given equation as,
TK D
A
B
.ln Pbar /=.ln 10/
C
where TK refers to T in kelvin, Pbar refers to pressure in bar, and the logarithm is natural. Next we use,
273:15/ C 32 and
TF D 1:8.TK
Pbar D
Ppsi
14:5
and substitute
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
Problem 1 Solution a) From steam tables at 40 bar we collect the following data:
600 C
650 C
3
40 bar 0:0989 m =kg 0:1049 m3 =kg
By interpolation at V D 100 g=cm3 D 0:1 m3 =kg we find
T D 600 C
650
0:1049
600
.0:1
0:0989
0:0989/ D 609:2 C
The system is at
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2015
Homework Set 5
Due: February 20
Reading: 3.13.7
Problems 3.12, 3.14, 3.22, in the book, and the problem below.
1
Problem 1 Solution a) The initial state is at its boiling point. The specific volume is
V1 D
1 m3
D 0:833333 m3 =kg
1:2
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2015
Homework Set 5
Due: February 20
Reading: 3.13.7
Problems 3.12, 3.14, 3.22, in the book, and the problem below.
Problem 4 a) Steam is compressed reversibly in a closed system at constant temperature T D 300 C from
20 bar to 30 bar. Ca
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2014
Homework Set 1
Due: Will not be collected
Reading: Chapter 3; sections 3.13.6
Problems 3.4, 3.5, 3.10, 3.18 in the book.
Exam Reminder
The first midterm exam is on Friday 02/13/15, 100 Thomas, 6:307:45 PM. The exam will cover chapter
Introduction to Chemical Engineering Thermodynamics
CH E 220

Spring 2015
ChE 220  Spring 2014
Homework Set 1
Due: January 23
Reading: Chapter 1; Chapter 2, section 2.1
Problem 1 Problem 1.2 in the book.
Problem 2 Problem 1.4 in the book.part (a) asks for a plot of the intermolecular potential. This plot should
be done on the