Chemical Engineering Department
Chemical Engineering Thermodynamics-II
Date:15-03-2021
Assignment –I
Marks:10
1. Consider a solution of two species S 1/S2 at 25oC such that x1 = 0.4. If
= 40 x 10-6 m3/mol,
find
.The solution specific gravity is = 0.90, and the molecular weights of the species are 32 and
18 respectively.
[CO3]
2. The molar enthalpy of a binary solution is given by:
V = 500 x1 + 1000 x2 + x1 x2 (50 x1+40x2) cm3/mol. Find the expressions for:
[CO3]
3. What is the change in entropy when 0.6 m3 of CO2 and 0.4 m3 of N2, each at 1 bar and 250C blend
to form a gas mixture at the same conditions? Assume ideal gases.
[CO1]
4. Estimate the fugacity of methane at 32 0C and 9.28 bar. Use the generalized correlation approach.
For methane Tc = 190.7 K, Pc = 46.41 bar, ω = 0.011
[CO2]
5.
For the following system compute the species fugacity coefficients for an equimolar mixture at 20 bar
and 500K.
[CO3]
Tc (K)
Pc ( bar)
Vc X 103 (m3/mol)
Zc
ω
yi
Propane (1)
369.9
42.57
0.2
0.271
0.153
0.4
Pentane (2)
469.8
33.75
0.311
0.269
0.269
0.6
6. Methanol (1)-acetone (2) system is described by the Van Laar activity coefficient
model. At 600C, the model parameters are
coefficients for a solution containing 10mole% of methanol.
7.
. Estimate the activity
[CO2]
For SO2 at 600 K and 300 bar, determine good estimates of the fugacity and of
/ RT.
[CO2]
GE
8. Estimate the fugacity of isobutylene as a gas:
(a) At 553.15 K (280°C) and 20 bar; (b) At 553.15 K (280°C) and 100 bar. [CO3]
Chemical Engineering Department
Chemical Engineering Thermodynamics-II
Date:15-03-2021
Assignment –I
Marks:10
9. The enthalpy of a binary liquid mixture containing components 1 and 2 at
298 K and 1.0 bar is given by
[CO3]
H = 400x1 + 600x2 + x1x2(40x1 + 4x2) where H is in J/mol.
Determine
(a) Pure component enthalpies
(b) Partial molar enthalpies.
10. Ethyl alcohol and hexane form an azeotrope at 33.2% (mol) ethanol. It
boils at 331.9 K at 101.3 kPa. At 331.9 K, the vapour pressures are 44.25 kPa
for ethanol and 72.24 kPa for hexane. Determine:
[CO2]
(a) The van Laar constants
(b) The vapour composition for a solution containing 50% (mol) hexane
boiling at 331.9 K
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