King Saud University
CHE304
College of Engineering
Time 2.0 Hr
Chemical Eng. Dept.
Final Exam
Date 25/1/1429 H
Chemical Engineering Thermodynamics for Petroleum Engineering
Instruction : Answer All Questions
Question One
Define The Following:
1- The Statement of The First Law of Thermodynamics
2- The Mathematical Statement of The First Law of Thermodynamics
3- State Function
4- Equilibrium
5- The Phase Rule
6- The reversible Process
7- Enthalpy
8- Heat Capacity
9- Open System
10- PV diagram for a pure substance
11- The Ideal Gas
12- Adiabatic Process
13- Sensible Heat
14- Latent Heat
15- The Statements of The Second Law of Thermodynamics
16- The Mathematical Statement of The Second Law of Thermodynamics
17- Thermal Efficiency
18- Entropy
19- Heat of Formation
20- Heat of Reaction
Question Two
Calculate the theoretical (maximum) flame temperature when methane (CH4) at 25 ºC
is burned with the theoretical amount of oxygen at 25 ºC.
Question Three
Calculate the standard heat of the methanol-synthesis reaction at 25 ºC.
Question Four
An ideal gas undergoes the following sequence of mechanically reversible process in
a closed system:
a) From an initial state of 70 ºC and 1 bar, it is compressed adiabatically to 150
ºC.
b) It is then cooled from 150 to 70 ºC at constant pressure.
c) Finally, it is expanded isothermally to its original state.
- Calculate W, Q, ΔU, ΔH for each of the three processes and for the
entire cycle.
- Sketch the PV diagram for the cycle.
Take Cv =12 J/mol K, Cp = 20 J/mol K.
Additional Data
The methanol-synthesis reaction : CO(g) + 2H2(g) - CH3OH(g)
R= 8.314 J/mol K = 83.14 cm3 bar mol-1K-1
1 J = 10 cm3 bar
Heat Capacities of Gases ( Cp/R = A + B T) where T in K
Chemical Species
A
103 B
CH4
1.70
9.08
CO2
5.46
1.05
H2O
3.47
1.45
CO
3.38
0.56
H2
3.25
0.422
CH3OH
2.20
12.20
O2
3.64
0.51
Standard Enthalpies of Formation at 298.15 K (J/mol of the substance formed)
Chemical Species
ΔHf298
CH4 (g)
-74520
CO2 (g)
-393509
H2O (g)
-241818
CO (g)
-110525
CH3OH (g)
-200600