Download GTU B.Tech 2020 Summer 5th Sem 2150501 Mass Transfer Operation I Question Paper

Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 5th Sem 2150501 Mass Transfer Operation I Previous Question Paper

Seat No.: ________
Enrolment No.___________

GUJARAT TECHNOLOGICAL UNIVERSITY
BE - SEMESTER? V EXAMINATION ? SUMMER 2020
Subject Code: 2150501 Date:27/10/2020
Subject Name: MASS TRANSFER OPERATION - I
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) Define molecular diffusion and eddy diffusion with examples.
03

(b) Differentiate between Direct and Indirect Mass transfer operations.
04

(c) State different theories explaining the meaning of mass transfer coefficients.
07
Explain any one in detail.

Q.2 (a) Explain temperature and pressure dependency of diffusivity of gases.
03

(b) Explain the concept of equilibrium in case of interphase mass transfer.
04

(c) State Fick's first law of diffusion and explain NA and JA. Also, prove that for
07
unidirectional binary diffusion JA = - JB.

OR

(c) In an O2 ? N2 gas mixture at 1 atm pressure and 250C, the concentration
07
of Oxygen at two planes 2 mm apart are 10 and 20 volume %
respectively. Calculate flux of diffusion of O2 for the case where N2 is
non-diffusing.
= 2.065 x 10-5 m2/s.
O
D 2 N2
Q.3 (a) What are different equipments used for gas-liquid mass transfer
03
operations?

(b) What is ideal liquid solution? Mention its characteristics.
04

(c) Explain stepwise procedure to find the minimum liquid gas ratio for gas
07
absorber with neat sketch.

OR

Q.3 (a) Mention different types of packings used in packed tower.
03

(b) What is absorption factor A in case of gas absorption?
04

(c) Explain the selection criteria for choice of solvent for gas absorption.
07
Q.4 (a) Mention various industrial liquid extraction equipments.
03

(b) Write a note on Caking of crystals.
04

(c) Define the
following terms:
07
Tray efficiency, murphree efficiency, coning, Weeping, Dumping,
flooding, entrainment

OR

Q.4 (a) Define: Liquid extraction, Extract, Raffinate
03

(b) Describe fundamentals of crystallization in brief.
04

(c) Differentiate between packed tower and tray tower.
07
Q.5 (a) What are industrial applications of liquid extraction?
03

(b) List out various factors to be considered in making choice of solvent for
04
liquid-liquid extraction.

(c) Explain counter current multiple contact Shanks system for leaching with
07
neat sketch.

OR
Q.5 (a) What is rate of leaching? Explain..
03
1

(b) Discuss the preparation of solids in leaching.
04

(c) Discuss the system of three liquids ? one pair partially soluble on ternary
07
Equilibria for liquid extraction.

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