IndiaBIX Chemical Engineering: Mass Transfer Section 12

Question 1

With increase in carbon percentage in steel, its
yield stress decreases.
elongation percent increases.
tensile strength increases.
impact strength increases.

Answer 1

tensile strength increases.

Question 2

Percentage of gaunge is maximum in the ore of
iron
gold
zinc
copper

Answer 2

gold

Question 3

The forms in which various metals and non metals occur in nature are called minerals. Which of the following is not a metallic ferrous mineral?
Cassiterite
Sphalerite
Chalcopyrite
Calcite

Answer 3

Calcite

Question 4

Pick out the wrong statement.
Dry bulb temperature, wet bulb temperature & dew point are the same in case of saturated air.
Dew point is reached by cooling the humid air at constant moisture content.
Heating of humid air is done for its dehumidification.
none of these.

Answer 4

Heating of humid air is done for its dehumidification.

Question 5

The most commonly used material for sewers for carrying sewage in the normal situation is
asbestos cement
stainiess steel
stoneware
cast iron

Answer 5

stoneware

Question 6

Filler metal is used in __________ welding.
braze
electric spot
projection
seam

Answer 6

braze

Question 7

Acetylene should never be conveyed through __________ pipe, as it forms an unstable compound that dissociates violently at the slightest shock.
stainless steel
copper
aluminium
brass

Answer 7

copper

Question 8

Which of the following contains the least percentage of carbon ?
Pig iron
Wrought iron
Cast iron
Malleable iron

Answer 8

Wrought iron

Question 9

Electric arc furnace is employed mainly for the production of __________ steel.
high carbon
alloy
mild
plain carbon

Answer 9

alloy

Question 10

Heat treatment of steel is done mainly to change its
mechanical properties.
physical properties,
chemical composition.
all ‘a’, ‘b’ & ‘c’.

Answer 10

mechanical properties.

Question 11

__________ method of depreciation calculation ensures that the interest is charged on the cost of machine asset every year on the book value, but the rate of depreciation remains constant every year.
Annuity charging
Atraight line
Ainking fund
None of these

Answer 11

Atraight line

Question 12

Main alloying element in Elinvar used in precision instruments, hair springs for watches etc. is
chromium
nickel
zinc
aluminium

Answer 12

nickel

Question 13

Color of brass changes from yellow to __________ after its dezincification which exemplifies selective leaching.
grey
red
orange
violet

Answer 13

red

Question 14

Heat dissipation in cooling towers is mainly by
conduction
convection
evaporation
radiation

Answer 14

evaporation

Question 15

In BOF, desiliconisation is a first order reaction. So the silicon content of the metal decreases
linearly with time.
exponentially with time.
logarithmically with time.
in proportion to the square root of time.

Answer 15

linearly with time.

Question 16

Hoope’s cell is predominantly used for the electrolytic refining of
zinc
copper
aluminium
tin

Answer 16

aluminium

Question 17

Lead percentage in pure galena is about
8.6
86.6
35.8
61.4

Answer 17

8.6

Question 18

Pick out the wrong statement.
Erosion corrosion which is identified by surface grooves, occurs due to the combined action of corrosive environment and mechanical abrasion.
Stress corrosion occurs due to the combined action of corrosive environment and the compressive stress.
Stainless steel is prone to stress corrosion in solution containing chloride ion.
In case of stress corrosion, the direction of crack propagation is perpendicular to the applied tensile stress.

Answer 18

Stress corrosion occurs due to the combined action of corrosive environment and the compressive stress.

Question 19

The life of a ball bearing is inversely proportional to
(load)1
(load)2
(load)3
(load)0.33

Answer 19

(load)3

Question 20

Pick out the wrong statement.
Partnership is suitable for medium size business.
A certain minimum of subscription of capital is required for legally starting a business in a Public Limited Joint Stock Company.
Public Limited Joint Stock Company is legally bound to issue prospectus after registration.
A small scale industry is the one, which has a minimum capital investment of Rs. 50 lakhs and maximum 100 lakhs.

Answer 20

A small scale industry is the one, which has a minimum capital investment of Rs. 50 lakhs and maximum 100 lakhs.

Question 21

Stoneware pipes used for sewers for carrying sewage normally is joined by __________ joint.
spigot and socket
flanged iron
collar
expansion

Answer 21

spigot and socket

Question 22

Which of the following parameters is actually measured during tensile testing of a specimen using Universal testing machine?
Load & elongation.
Engineering stress & strain.
True stress & strain.
Poisson’s ratio & Young’s modulus.

Answer 22

Load & elongation.

Question 23

End cooler’ or ‘after cooler’ is employed in air compressor mainly to
remove oil vapour or moisture from air.
cool the dry air before use.
reduce the volumetric capacity of receiver.
none of these.

Answer 23

remove oil vapour or moisture from air.

Question 24

Streaklines, streamlines & pathlines are almost identical for __________ fluid flow.
ideal
uniform
steady
none of these

Answer 24

steady

Question 25

The suction and delivery pressure for a two stage compressor are 1 and 25 atm respectively. The intermediate stage pressure would be around __________ atm. 5 10 15 20

Answer 25

5

Question 26

The term 'Value' in value engineering technique refers to the __________ cost of the product. function (utility) selling production total

Answer 26

function (utility)

Question 27

Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8 °C °F °K °R

Answer 27

°F

Question 28

The entropy change for a spontaneous process is > 0 for the system. < 0 for the system. > 0 for the system & the surrounding. < 0 for the system & the surrounding.

Answer 28

< 0 for the system & the surrounding.

Question 29

Milligram of KOH required to saponify 1 gm of oil is called its __________ number. saponification acid precipitation emulsion

Answer 29

saponification

Question 30

Pick out the wrong statement about a fast breeder reactor. uses molten sodium as moderator. converts fertile fuel into fissile fuel. requires highly enriched fuel. produces more fuel than it consumes.

Answer 30

uses molten sodium as moderator.

Question 31

The speed of sound will be maximum in vacuum metal air water

Answer 31

metal

Question 32

Work done by a/an __________ process is determined by. adiabatic quasi-static isothermal isentropic

Answer 32

quasi-static

Question 33

In case of water (Prandtl number ≈ 6) flowing over a flat plate heated over the entire length, the thermal boundary layer thickness as compared to hydrodynamic boundary layer thickness is less more equal unpredictable

Answer 33

less

Question 34

__________ number is sometimes used in place of Grashoff number in free convection heat transfer. Stanton Brinkman Rayleigh Nusselt

Answer 34

Rayleigh

Question 35

Wrought iron does not have the uniform strength in all directions. ability to hold protective coating. high ductility & corrosion resistance. easily weldable characteristics.

Answer 35

uniform strength in all directions.

Question 36

Nitriding of steel is a process for case hardening spheroidising normalising annealing

Answer 36

case hardening

Question 37

The maximum percentage of chromium that can be added to steel is about 12 18 24 30

Answer 37

18

Question 38

Holes in a plate for rivetted joints is preferably made by drilling tapping reaming punching

Answer 38

drilling

Question 39

The temperature at which a gas, when subjected to Joule-Thomson expansion, neither cools or heats up, is termed as the __________ temperature. Above this temperature the gas heats up on throttling and below this the gas cools down. isotactic saturation inversion throttling

Answer 39

inversion

Question 40

Source of heat supply in a cupola is coke charcoal lumpy coal pulverised coal

Answer 40

coke

Question 41

Machine tool bodies are usually made of cast iron mild steel wrought iron copper alloys

Answer 41

cast iron

Question 42

Out of the following, the best material capable of withstanding shock & vibration without the danger of cracking is malleable iron grey cast iron chilled cast iron white cast iron

Answer 42

malleable iron

Question 43

On increasing the yield strength of a steel from 450 to 650 MPa, its __________ will increase. ultimate tensile strength (UTS) modulus of toughness percent elongation modulus of resilience

Answer 43

modulus of toughness

Question 44

The refractory brick which has good thermal shock resistance at high temperature but cracks on cooling below 400°C is magnesite chrome silica fireclay

Answer 44

silica

Question 45

The path and movements followed by men, materials & equipments in executing the activities is indicated by the travel charts man-machine charts string diagram flow diagram

Answer 45

flow diagram

Question 46

No cutting fluid is normally used, while machining cast iron aluminium mild steel stainless steel

Answer 46

cast iron

Question 47

An orthotropic material is a special class of anisotropic material, which is described by their properties in three perpendicular directions. An example of orthotropic material is stainless steel cast iron wood teflon

Answer 47

wood

Question 48

pH value of rain water in India ranges from 5.5 to 7.5 8 to 9.5 3.5 to 5 9.5 to 10.5

Answer 48

5.5 to 7.5

Question 49

The capital & running costs of similar machines having unequal service life can be compared by the __________ method. equivalant annual cost rate of return present net worth capitalised cost

Answer 49

capitalised cost

Question 50

Pick the odd man out. Austempering Martempering Cyniding Parkerizing

Answer 50

Parkerizing