Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 6th Sem 2160506 Chemical Reaction Engineering I Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VI (NEW) EXAMINATION ? WINTER 2020
Subject Code:2160506 Date:03/02/2021
Subject Name:Chemical Reaction Engineering - I
Time:02:00 PM TO 04:00 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
MARKS
Q.1 (a) Discuss the classification of Chemical Reaction based on
03
Thermodynamics and Stoichiometry with suitable examples of
each.
(b) Define Rate of Reaction based on various component and also
04
gives comparison of its.
(c) Derive an expression showing effects of temperature on heat of
07
reaction from thermodynamics.
Q.2 (a) What is rate equation? Also mention unit of rate of reaction and
03
rate constant for first, second and third order elementary
chemical reactions.
(b) Milk is pasteurized if it is heated to 63oC for 30 min, but if it is
04
heated to 74oC it only needs 15 sec for the same result. Find the
activation energy of this sterilization process.
(c) Discuss the Activation energy and Temperature dependency of
07
rate constant.
Q.3 (a) Define zero order reaction with suitable example.
03
(b) Discuss the method for rate equation interpretation of
04
irreversible unimolecular first order elementary reaction by
integral method of analysis.
(c) Experimental studies of a specific decomposition of A in a batch
07
reactor using pressure units show exactly the same rate at two
different temperatures:
At 400K -
2
= 2.3
At 500K -
2
= 2.3
Where unit of ?rA is mol/m3.sec and unit of PA is atm.
(a) Evaluate the activation using these units
(b) Transform the rate expression into concentration units
and then evaluate the activation energy.
Q.4 (a) Discuss the chemical reaction classification based on
03
molecularity with suitable examples of each.
(b) Discuss the differential method for interpretation of rate
04
equation of nth order unimolecular chemical reaction.
(c) The first order reversible liquid reaction
07
1
A R, CAO = 0.5 mol/liter, CRO=0
takes place in a batch reactor. After 8 minutes, conversion of A
is 33.3% while equilibrium conversion is 66.7%. Find the rate
equation for this reaction.
Q.5 (a) Compare batch reactor and steady state flow reactors.
03
(b) Discuss the space velocity and space time for steady state flow
04
reactors.
(c) An aqueous feed of A and B (44 liter/min, 100mmol A/liter,
07
200mmol B/liter) is to be converted to product in a plug flow
reactor. The kinetics of the reaction is represented by
A + B R,
- = 200
.
Find the volume of reactor needed for 99.9% conversion of A to
product.
Q.6 (a) Compare between space time of mixed flow reactor and time
03
constant in mixing process without chemical reaction.
(b) Compare ideal batch reactor performance of constant and
04
variable density reaction.
(c) At 650 oC phosphine vapor decomposes as follows:
07
4PH3 P4(g) +6H2, - = (10 -1)
What size of plug flow reactor operating at 649oC and 11.4 atm
is needed for 75% conversion of 10 mol/hr of phosphine in a 2/3
phosphine and 1/3 inert feed?
Q.7 (a) Discuss autocatalytic reactor.
03
(b) Prove that N number of plug flow reactor connected in series and
04
its total volume V gives the same conversion as a single plug
flow reactor of volume V.
(c) Derive the performance equation for steady state mixed flow
07
reactor for constant and variable density system and compare its
graphical representation.
Q.8 (a) Differentiate between homogeneous reaction and heterogeneous
03
reaction.
(b) Discuss the effect of temperature and composition on single
04
homogeneous reaction.
(c) Derive the performance equation of recycle reactor and discuss
07
tis graphical representation for constant and variable density.
*************
2
This post was last modified on 04 March 2021