Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 5th Sem 2150503 Chemical Engineering Thermodynamics Ii Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE - SEMESTER? V EXAMINATION ? SUMMER 2020
Subject Code: 2150503 Date:29/10/2020
Subject Name: CHEMICAL ENGINEERING THERMODYNAMICS - II
Time: 02:30 PM TO 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
MARKS
Q.1 (a) What are the characteristics of an ideal solution ?
03
(b) Discuss any two methods to determine fugacity of pure gases.
04
(c) Answer the followings:
07
1 What do you mean by activity of pure fluid? How would you
02
estimate activity of an incompressible fluid?
2 How activity coefficient is related to the molar Excess Gibbs
01
free energy in solution ?
3 Why does the boiling point diagram at high pressures lie above
01
that at a lower pressure?
4 What do you mean by "extent of reaction "?
01
5 What is the degree of freedom for the following non ?reactive
01
equilibrium system?
Two partially miscible liquid phases are in equilibrium with
vapor phase.
6 How would you predict the feasibility of reaction from the value 01
of the standard free energy change?
Q.2 (a) Discuss effect of increasing pressure on T-x-y diagram in brief.
03
(b) Discuss Lewis-Randall rule, clearly mentioning its limitations.
04
(c) Define "Partial Molar property". Describe different methods to
07
determine partial molar properties in detail.
OR
(c) Derive the equation for the criteria for phase equilibrium in terms
07
of fugacity for mixture of N components and phases
Q.3 (a) Discuss any two methods to check consistency of experimental
03
VLE data in detail.
(b) Discuss effect of temperature and pressure on chemical potential.
04
(c) Prove that if Henry's law is obeyed by component 1 in a binary
07
solution over certain concentration range, Lewis-Randall rule
will be obeyed by component 2 over the same concentration
range.
OR
Q.3 (a) Discuss excess Gibbs free energy in brief.
03
(b) Discuss effect of temperature and pressure on equilibrium
04
constant.
(c) Discuss van Laar and Margulies Equations in detail.
07
Q.4 (a) Discuss phase rule for non reacting systems in brief.
03
1
(b) Derive equations for flash calculations.
04
(c) The vapour pressures of acetone(1) and acetonitrile (2) can be
07
evaluated by the following Antoine equations, where P is in
kPa and T is in K.
2940.46
1 = 14.5463 -
- 35.93
2945.47
2 = 14.2724 - - 49.15
Assuming ideal solutions, calculate
1) 1 and 1 at 327 K and 65 kPa 2) T and y1 at 65 kPa and
x1= 0.4 3) P and 1 at 327 K and 1 = 0.4
OR
Q.4 (a) Discuss Duhem's Theorem briefly.
03
(b) Write short note on VLE for completely immiscible systems with
04
neat diagram.
(c) The partial molar volumes of acetone and chloroform in a
07
mixture in which mole fraction of acetone is 0.5307 are 74.166?
10 ? 6 m3/mol and 80.235 ? 10 ? 6 m3/mol respectively. What is
the volume of 1 kg of the solution?
Q.5 (a) Discuss effect of presence of Excess of reactants and products on
03
equilibrium conversion.
(b) Wilson's parameters 12 and 21 for the system nitromethane (1)
04
and carbon tetrachloride(2) at 45 are 0.1156 and 0.2879
respectively. Calculate the activity coefficients of the
components in a solution containing 30 mol % nitromethane.
(c) Derive equation for standard heat of reaction.
07
OR
Q.5 (a) Discuss Heterogeneous reaction equilibria with reference to
03
"reactions in solutions".
(b) Calculate the fugacity of pure ethylene at 100 bar and 373 K.The
04
van der Waals constants are a = 0.453 J m3/mol2 and b = 0.571
? 10-4 m3/mol and molar volume at 100 bar and 373 K = 2.072
? 10-4 m3/mol.
(c) Discuss minimum and maximum boiling azeotropes with neat
07
sketch.
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This post was last modified on 04 March 2021