King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1427/1428H
Tutorial 1
1. One mole of Heptane (C7H16) is reversibly evaporated at its boiling point of 98C
under atmospheric pressure. The latent heat if n-heptane at the boiling point is 3.098x105
J/kg. Calculate the values of q, w, ∆H, ∆S, ∆G for this process.
( ∆G = ∆H-T∆S)
2. What is the theoretical maximum work available from 1 mole of an ideal gas
(Cv=2.903x 104 J/kgmole K) at 100C and 10 bar in surroundings at 1 bar, 0C.
3. Calculate the minimum work required to convert 1gmole of oxygen gas at 298.15K
and 1 atmosphere to the liquid state at 90.13K in a reversible process in which heat is
transferred to a heat reservoir at 298.15
Cp for oxygen gaseous = 6.96 cal/mole K, Entropy of vaporization at the normal
boiling point (90.13K) = 18.07 Cal/mole.K.
King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1427/1428H
Tutorial 2
Q1- a) If a gas obeys the equation,
nRT
n2 A
(1)
P
 2
V  nB V
Find expression for (
Hint use: ( (
U
)T
V
and
U
P
) T  T ( )V  P
V
T
(
H
)T
P
and (
H
V
)T  V  T ( ) P )
P
T
b) -Carbon dioxide obeys the Van der Waal equation (1) . Derive expressions for the
change of the specific entropy and change of the specific internal energy of this gas.
-If carbon dioxide of 266 F has a specific volume of 0.0137m3/kg and on compression to
333K then has a specific volume of 0.0106m3/kg, find the change in specific entropy and
specific internal energy of the gas
- (Data Cv =0.66Kj/Kg C, a=0.182 Kj/KG, b= 1.89x10-4 m3/kg, R=0.189 Kj/Kg.K)
Q2 A developed EOS for gases is proposed as follows
Z  1
P a
(  b)
R T
Where a and b are constants that depend on the gas. It is suggested that the following
entropy relation hold for the proposed EOS,
S
RP
 aP  K
T
K= Constant
a) Check the consistency of the proposed EOS
b) Determine the changes in internal, enthalpy, Gibbs energy using the proposed
EOS.
Q3. Determine the pressure in a 40 liters vessel containing 1kg of gaseous ethane at 68C
using,
- Ideal gas equation,
- Van Der Walls EOS
- The Redlich Kwong EOS
- Generalized correlation
Data; Tc (K)= 305.3K, Pc=48.72Bar, Zc=0.279
ω =0.100
King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1427/1428H
Tutorial 3
Q1.Determine the vapor pressure in KPa for benzene at 0C, 10C, 50C, 100C, and 120C,
using the Antoine equation
Data: Constants for Antoine equation A= 13.7819, B=2726.81 C=217.572
(Valid for temp range 6C to 104C).
Q2-Calculate the fugacity of nitrogen at -120C and pressures of 20 and 60atm using the
flowing date, through an analytical method
P atm
Z = PV/MRT
0
1.0
15
0.94
25
0.91
30
0.89
45
0.84
60
0.78
68
0.76
Q3. The density of phenol is 1.072 in the solid form and 1.056 in the liquid form. Its heat
of fusion is 24.9cal/gm, and its melting point is 41C. Calculate the effect of pressure on
the melting point in degree per atmosphere.
Q4. The melting points of carbon tetrachloride at various pressures are given below with
the volume change associated with fusion. Find ∆H and ∆S for the fusion of
1 kgmole of carbon tetrachloride at a) 1 atms, b) 6000atmos.
P bar
1
TC
-22.6
∆Vm3/kmole(103) 3.97
1000
-15.3
3.06
2000
48.9
2.51
5000
130.8
1.52
7000
176.2
1.08
King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1427/1428H
Tutorial 4
Q1 Consider the system methanol(1) / methyl acetate (2). The activity coefficients are
given by the following equations
ln  1  Ax22
and
ln  2  Ax12
with A = 2.771 – 0.00523T
The Antoine equations are given by :
lnP1(sat) (Kpa) = 16.592 – 3643.3/(T (K) – 33.42)
and ln P2 (sat) (kPa) = 14.25 – 2665.54/T – 53.42
-Calculate
a) Bubl T T= 45C and x1= 0.35
b) Dew P T=45C and y1=0.50
c) Bubl T, P=101.33KPa and x1=0.80
d) Dew T; P= 101.33Kpa and y1= 0.45
Q2. Use the DePriester Charts to determine the Bulb P, and the Dew P, for a mixture of
methane (0.10), propane (0.5) and ethane at 60F
Q3 Fit the following data for methanol(1) / benzene(2) system at 90C to the following
models, one parameter Margules, two parameter Margules, Van laar.
P mmHg
x1
y1
1865
0.117
0.502
2113 2218 2273
0.257 0.376 0.549
0.594 0.618 0.650
2292 2208
0.707 0.856
0.689 0.765
King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1426/1427H
Tutorial 5
Q1 Consider the system methanol(1) / methyl acetate (2). The activity coefficients are
given by the following equations
ln  1  Ax22
and
ln  2  Ax12
with A = 2.771 – 0.00523T
The Antoine equations are given by :
lnP1(sat) (Kpa) = 16.592 – 3643.3/(T (K) – 33.42)
and ln P2 (sat) (kPa) = 14.25 – 2665.54/T – 53.42
-Calculate
a) Bubl T T= 45C and x1= 0.35
b) Dew P T=45C and y1=0.50
c) Bubl T, P=101.33KPa and x1=0.80
d) Dew T; P= 101.33Kpa and y1= 0.45
Q2.
Use the DePriester Charts to determine the Bulb P, and the Dew P, for a mixture of
methane (0.10, methane (0.5) and ethane at 60F
King Saud University- College of Engineering- Chemical Eng.
Che 501 Advanced Chemical Engineering Thermodynamics
Spring 1426/1427H
Tutorial 6
Q1. 1.165 Kg moles of nitrogen and 0.465 kg moles of hydrogen are equilibrated in a
1m3 vessel at 450C. At equilibrium 0.0845 kgmoles of ammonia is present. Determine
the amounts of nitrogen and hydrogen present and the partial pressures of all components
at equilibrium.
Q2 For the reaction
2H2(gas) + O2(gas) = 2H2O (gas)
The value of Kp at 1727C is 1.55x107, partial pressures being measured in atmospheres.
Calculate ∆G and ∆G when two moles of hydrogen at 0.10 atmospheres react with one
mole of oxygen at 0.10 atmosphere to form water vapor at 1 atmosphere, the temperature
being 1727C.
Q3.Calculate the standard free energy change at 627C for the following reaction
N2(gas) + 3H2 (gas) = 2NH3(gas)
-
From the following data
∆H 298 = - 21900cal
∆G 298= -7820 cal
For N2, Cp= 6.5 + 0.0010T Cal/ degree per mole
H2 Cp = 6.50 + 0.0009T Cal/ degree per mole
NH3 Cp = 8.04 + 0.0007T + 0.0000051T2 cal/degree per mole