Home exam iii
Chemical engineering thermodynamics i
Che 203
Submit before 25/12/2012
Q1
A -Find the molar volume of saturated liquid and that of saturated vapor by the Redlich/kwong equation for one of the following and compare results with values found by suitable generalized correlations:
1-isobutane at (n+m+l)*4 C ,Psat can be found via Antoine equation?.
2-toluene at (n+m+l)*3.5 C ,Psat can be estimated from Antoine ?. b-calculate the volume occupied by(n+m+l ) kg. of Propane at (n+m)*6 C and (m+l)2.5 bar.
And the mass of ethylene contained in a 0.5 m3 cylinder at (n+l)*4 C and( m+l)10 bar ?.
Q2- Air initially at (n+m+l)*1.2 C and (n+m+l)*3.5 kPa ,undergoes the following cyclic process in a closed system through the following steps:
1-reversible compression adiabatically to (n+m+L)*20 kPa , then cooled at constant pressure to the initial temperature reversibly , and finally expanded isothermally and reversibly to its original state.
2- the cycle traverses exactly the same changes in state, but each step is irreversible with an efficiency of 75% compared with the corresponding reversible processes in part- 1, the initial step can no longer be adiabatic.. calculate Q,W,ΔU ,ΔH for each step of the process and for the cycle ,take
Cp=Cv+R, Cv=5/2 R.

Q3- Calculate the amount of heat required to raise the temperature of a stream of propane from (n+m+l) C to(n+m+l)*25 C flowing with a flow rate of 500kg/h.
Q4- what is the maximum flame temperature that can be reached by the combustion of ethane with (m+l) % excess O2? Both air and ethane enter the burner at 30 C?
Q5-In Ethane reforming at high temperature and 1 atm. pressure the reactions to take place are :
C
2
H
6
+2H
2
O→→2 CO+ 5H
2
The only side reaction expected to take place is :
CO+ H
2
O →→CO
2
+H
2
, both reactions are to take place in the gas phase. Reactants are supplied in the ratio, 3 mole steam to 1 mole Ethane , the temperature in the reactor is kept constant and is equal to(n+mL)*42 K by the continuous addition of heat .The Ethane is completely converted and the product stream contains
(n+m)*1.3 mole% CO. reactants enter the reactor at 650 K.
Calculate the heat effects in the reactor?.
Q6-Example 4-9 with the following differences : the average analysis on dry basis is (m+l)*1.08 mole %CO2, 0.(m+n) mole %CO,n mole% O2, and balance N2. Calculate the fraction of heat of combustion of oil transferred as heat to the boiler ?
Dr jamal amous