Chemical Heat Transfer MCQs

Option A: Admit the feed

Option B: Remove the product

Option C: Facilitate removal of non-condensable gases

Option D: Create vacuum

Correct Answer: Facilitate removal of non-condensable gases ✔

Option A: Increases

Option B: Decreases

Option C: Remains unchanged

Option D: Increases exponentially

Correct Answer: Decreases ✔

Option A: Infinity

Option B: Zero

Option C: Same as average heat transfer co-efficient for tube side

Option D: None of these

Correct Answer: Infinity ✔

Option A: Liquid density

Option B: Liquid viscosity

Option C: Hot surface temperature

Option D: Interfacial tension

Correct Answer: Interfacial tension ✔

Option A: Type of absorbing surface

Option B: Distance between the heat source and the object receiving the heat

Option C: Surface area and temperature of the heat source

Option D: None of these

Correct Answer: None of these ✔

Option A: 1

Option B: 2

Option C: 1/2

Option D: 4

Correct Answer: 2 ✔

Option A: Brinkman number

Option B: Stanton number

Option C: Schmidt number

Option D: Peclet number

Correct Answer: Schmidt number ✔

Option A: Antoine

Option B: Kopp’s

Option C: Lee’s

Option D: Kistyakowsky

Correct Answer: ✔

Option A: Temperature distribution is independent of time

Option B: Temperature distribution is dependent on time

Option C: Heat flows in one direction only

Option D: Three dimensional heat flow is concerned

Correct Answer: Temperature distribution is dependent on time ✔

Option A: Tube thickness

Option B: Cross-sectional area

Option C: Weight per unit length

Option D: None of these

Correct Answer: Cross-sectional area ✔

Option A: t = 283 s

Option B: t = 356 s

Option C: t = 400 s

Option D: t = 800 s

Correct Answer: t = 800 s ✔

Option A: 1 to 2

Option B: 5 to 10

Option C: 100 to 500

Option D: 1000 to 2000

Correct Answer: 5 to 10 ✔

Option A: Same

Option B: Different

Option C: Never different

Option D: Linearly related

Correct Answer: Different ✔

Option A: 520

Option B: 200

Option C: 400

Option D: 500

Correct Answer: 400 ✔

Option A: Clean and dirt free

Option B: Smooth clean

Option C: Contaminated cooling

Option D: Polished

Correct Answer: Contaminated cooling ✔

Option A: 0.1

Option B: > 1

Option C: < 1

Option D: 1

Correct Answer: 0.1 ✔

Option A: Viscosity

Option B: Density

Option C: Thermal conductivity

Option D: Corrosive nature

Correct Answer: Viscosity ✔

Option A: Decrease

Option B: Increase

Option C: First decrease and then increase

Option D: First increase and then decrease

Correct Answer: First increase and then decrease ✔

Option A: Feed is introduced in the first effect

Option B: Feed flows from low pressure to high pressure

Option C: No pumps are required between successive effects

Option D: None of these

Correct Answer: Feed flows from low pressure to high pressure ✔

Option A: 0.5

Option B: 1

Option C: 0

Option D: 2

Correct Answer: 1 ✔

Option A: Basket type

Option B: Horizontal tube

Option C: Short tube vertical

Option D: Long tube vertical

Correct Answer: Horizontal tube ✔

Option A: Large scale evaporation of liquor is needed

Option B: Corrosive liquids are to be concentrated

Option C: Fuel is cheaply available

Option D: Evaporation on small scale is to be done

Correct Answer: Large scale evaporation of liquor is needed ✔

Option A: 1.49

Option B: 1

Option C: 4.88

Option D: None of these

Correct Answer: 1.49 ✔

Option A: Black & smooth

Option B: Black & rough

Option C: White & smooth

Option D: White & rough

Correct Answer: Black & rough ✔

Option A: The cooling rate will be the same for the two spheres and hence the two spheres will have

Option B: Both the spheres will emit equal amount of radiation per unit time in the beginning

Option C: Both will absorb equal amount of radiation from the surrounding in the beginning

Option D: Both B. & C.

Correct Answer: D. Both B. & C. ✔

Option A: Brick

Option B: Air

Option C: Water

Option D: Silver

Correct Answer: Silver ✔

Option A: Avoid cavitation

Option B: Avoid frequent priming

Option C: Create more suction head

Option D: None of these

Correct Answer: Create more suction head ✔

Option A: Steam pressure

Option B: Feed temperature

Option C: Number of effect

Option D: Both B. & C.

Correct Answer: D. Both B. & C. ✔

Option A: Non-dimensional factor

Option B: Factor of safety

Option C: Conversion factor for individual film heat transfer co-efficient to overall heat transfer coefficient

Option D: None of these

Correct Answer: Factor of safety ✔

Option A: Buffer zone

Option B: Turbulent core

Option C: Both A. and B.

Option D: Viscous sub-layer

Correct Answer: Viscous sub-layer ✔

Option A: Atmospheric

Option B: Sub-atmospheric

Option C: Negative

Option D: Very high

Correct Answer: Very high ✔

Option A: Thickness of the wall

Option B: Area of the wall perpendicular to heat flow

Option C: Material of the wall

Option D: Temperature difference between the two surfaces of the wall

Correct Answer: Temperature difference between the two surfaces of the wall ✔

Option A: 1

Option B: < 1

Option C: > 1

Option D: > 5

Correct Answer: 1 ✔

Option A: High viscosity liquid is to be cooled

Option B: Requirement of heat transfer area is low

Option C: Overall heat transfer co-efficient is very high

Option D: A corrosive liquid is to be heated

Correct Answer: Requirement of heat transfer area is low ✔

Option A: Decreases

Option B: Increases

Option C: Increases exponentially

Option D: Remain unaffected

Correct Answer: Decreases ✔

Option A: Decreases

Option B: Increases

Option C: Remains unchanged

Option D: Increases exponentially

Correct Answer: Decreases ✔

Option A: d2T/dZ2 > 0

Option B: d2T/dZ2 = 0

Option C: d2T/dZ2 < 0

Option D: dT/dZ = 0

Correct Answer: d2T/dZ2 = 0 ✔

Option A: Resistances in parallel

Option B: Capacitors in series

Option C: Resistances in series

Option D: None of these

Correct Answer: Resistances in series ✔

A. 1
B. 1
D. None of these

Correct Answer: 1 ✔

Option A: High viscosity

Option B: High co-efficient of thermal expansion

Option C: Low temperature gradients

Option D: Low density change with temperature

Correct Answer: High co-efficient of thermal expansion ✔

Option A: St = f/2

Option B: St = f/4

Option C: St = 4f

Option D: St = f1/2

Correct Answer: St = f/2 ✔

Option A: Total condenser

Option B: Vacuum evaporator

Option C: Partial condenser

Option D: Double pipe heat exchanger

Correct Answer: Partial condenser ✔

Option A: The heat transfer rate is low in view of the large temperature drop

Option B: It is difficult to maintain

Option C: It is not economic

Option D: None of these

Correct Answer: The heat transfer rate is low in view of the large temperature drop ✔

Option A: Heat sensitive material can be handled

Option B: There is no additional cost of pumping

Option C: Most concentrated liquid is at highest temperature

Option D: Equal heat transfer co-efficients exist in various effects

Correct Answer: Most concentrated liquid is at highest temperature ✔

Option A: Increases

Option B: Decreases

Option C: Does not affect

Option D: May increase or decrease, depends on the type of baffle

Correct Answer: Increases ✔

Option A: Increases

Option B: Decreases

Option C: Remains unchanged

Option D: May increase or decrease; depending on temperature

Correct Answer: Increases ✔

Option A: 3 × 105

Option B: 3 × 108

Option C: 3 × 1010

Option D: 3 × 1012

Correct Answer: 3 × 108 ✔

Option A: Facilitate cleaning of the exchanger

Option B: Increase the heat transfer area

Option C: Relieve stresses caused by thermal expansion

Option D: Increase log mean temperature gradient

Correct Answer: Relieve stresses caused by thermal expansion ✔

Option A: Bleed point

Option B: Vent

Option C: Catchall

Option D: Baffle

Correct Answer: Catchall ✔

Option A: Smaller than

Option B: Greater than

Option C: Equal to

Option D: Not related with

Correct Answer: Smaller than ✔

Option A: Continues to increase

Option B: Continues to decrease

Option C: Goes through a minimum

Option D: Goes through a maximum

Correct Answer: Goes through a minimum ✔

Option A: Is a dimensionless quantity

Option B: Does not provide a safety factor for design

Option C: Accounts for additional resistances to heat flow

Option D: None of these

Correct Answer: Accounts for additional resistances to heat flow ✔

Option A: Remains unchanged

Option B: Increases

Option C: Increases or decreases depending on number of shell passes

Option D: Decreases

Correct Answer: Decreases ✔

Option A: J/M2°K

Option B: W/m2°K

Option C: W/m°K

Option D: J/m°K

Correct Answer: W/m2°K ✔

Option A: Double pipe

Option B: Plate fine

Option C: Series and parallel set of shell and tube

Option D: None of these

Correct Answer: Series and parallel set of shell and tube ✔

Option A: Increases

Option B: Decreases

Option C: Remains unchanged

Option D: May increase or decrease; depends on the solid

Correct Answer: Decreases ✔

Option A: Get economical temperature difference by using moderate pressure steam

Option B: Facilitate forward feeding in multiple effect evaporation

Option C: Concentrate heat sensitive materials

Option D: Achieve very high concentration of the final product

Correct Answer: Get economical temperature difference by using moderate pressure steam ✔

Option A: Capacity

Option B: Rate of evaporation

Option C: Economy

Option D: Rate of vaporisation

Correct Answer: Economy ✔

Option A: Laminar

Option B: Transition

Option C: Both A & B

Option D: Highly turbulent

Correct Answer: Highly turbulent ✔

Option A: Reynolds number

Option B: Prandtl number

Option C: Grashoff number

Option D: None of these

Correct Answer: Grashoff number ✔

Option A: C/E

Option B: E/C

Option C: CE

Option D: 1/CE

Correct Answer: C/E ✔

Option A: Prandtl number

Option B: Grashoff number

Option C: Thermal conductivity

Option D: Viscosity

Correct Answer: Prandtl number ✔

Option A: 25°C

Option B: 30°C

Option C: 35°C

Option D: 40°C

Correct Answer: 35°C ✔

Option A: Twice

Option B: Four times

Option C: Square root of

Option D: Square of

Correct Answer: Four times ✔

Option A: IR

Option B: I2R

Option C: IR2

Option D: I2R2

Correct Answer: I2R ✔

Option A: Painting the surface black

Option B: Painting the surface white (with aluminium paint)

Option C: Giving the surface a mirror finish

Option D: Roughening the surface

Correct Answer: Painting the surface white (with aluminium paint) ✔

Option A: Convection

Option B: Radiation

Option C: Conduction

Option D: All A., B. & C.

Correct Answer: Conduction ✔

Option A: Temperature of the body only

Option B: Wavelength of monochromatic radiation

Option C: Both A. and B.

Option D: Nature of material of body

Correct Answer: Temperature of the body only ✔

Option A: Film boiling

Option B: Nucleate boiling

Option C: Vapour binding

Option D: None of these

Correct Answer: Nucleate boiling ✔

Option A: Temperature

Option B: Porosity

Option C: Both A. & B.

Option D: Neither A. nor B.

Correct Answer: C. Both A. & B. ✔

Option A: Surrounding temperature

Option B: Average temperature of the fin

Option C: Temperature of the fin end

Option D: Constant temperature equal to that of the base

Correct Answer: Constant temperature equal to that of the base ✔

Option A: Feed

Option B: Depth of liquid over heating surface

Option C: Pressure difference between steam chest and vapour space

Option D: All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

Option A: Length

Option B: Area

Option C: Volume

Option D: None of these

Correct Answer: Area ✔

Option A: Remove condensate from the steam pipelines

Option B: Create vacuum

Option C: Superheat the steam

Option D: None of these

Correct Answer: Create vacuum ✔

Option A: Vertical heat exchanger with steam on tube side

Option B: Vertical heat exchanger with steam on shell side

Option C: Horizontal heat exchanger with steam on tube side

Option D: Horizontal heat exchanger with steam on shell side

Correct Answer: Vertical heat exchanger with steam on shell side ✔

Option A: Gases

Option B: Solids

Option C: Liquids

Option D: Both B. and C.

Correct Answer: D. Both B. and C. ✔

Option A: Isothermal

Option B: Non-isothermal

Option C: Both A. and B.

Option D: Neither A. and B.

Correct Answer: C. Both A. and B. ✔

Option A: 0.5

Option B: 0.05

Option C: 0.1

Option D: 0.15

Correct Answer: 0.1 ✔

Option A: √(ΔT1 . ΔT2)

Option B: 2 (ΔT1 . ΔT2)/(ΔT1 + ΔT2)

Option C: 2 (ΔT1 . ΔT2)/(ΔT1 – ΔT2)

Option D: (ΔT1 – ΔT2)/(ΔT1 . ΔT2)

Correct Answer: 2 (ΔT1 . ΔT2)/(ΔT1 + ΔT2) ✔

Option A: ha = hl

Option B: ha = 2hl

Option C: ha = 0.5 hl

Option D: ha = 0.75 hl

Correct Answer: ha = 2hl ✔

Option A: (ΔT)1/4

Option B: (ΔT)1/2

Option C: (ΔT)5/4

Option D: (ΔT)3/4

Correct Answer: (ΔT)3/4 ✔

Option A: Viscosity

Option B: Density

Option C: Thermal conductivity

Option D: Heat capacity

Correct Answer: Density ✔

Option A: 555

Option B: 55.5

Option C: 0.55

Option D: 0.15

Correct Answer: 0.15 ✔

Option A: Prandtl

Option B: Nusselt

Option C: Stanton

Option D: Grashoff

Correct Answer: Prandtl ✔

Option A: Zero

Option B: One

Option C: ∞

Option D: Between 0 and ∞

Correct Answer: Zero ✔

Option A: 5.6697 × 10-8W/m2.°K4

Option B: 0.1714 × 10-8W/m2.°K4

Option C: 5.6697 × 10-8kcal/m2. °K4

Option D: 0.1714 × 10-8kcal/m2. °K4

Correct Answer: 5.6697 × 10-8W/m2.°K4 ✔

Option A: 5.6

Option B: 0.025

Option C: 3.5

Option D: 0.0035

Correct Answer: 0.025 ✔

Option A: Plate type

Option B: Double pipe type with fin on steam side

Option C: Double pipe type with fin on air side

Option D: Shell and tube type

Correct Answer: Double pipe type with fin on air side ✔

Option A: Agitated film evaporator

Option B: Long tube vertical evaporator

Option C: Open pan evaporator

Option D: None of these

Correct Answer: Long tube vertical evaporator ✔

Option A: 1000

Option B: 727

Option C: 800

Option D: 1200

Correct Answer: 1000 ✔

Option A: Increases rapidly with temperature rise

Option B: Decreases rapidly with temperature rise

Option C: In independent of pressure

Option D: Both B. and C.

Correct Answer: Increases rapidly with temperature rise ✔

Option A: Facilitate the cleaning of outer tube surface

Option B: Enhance turbulence

Option C: Hold the tubes in position

Option D: All A , B & C

Correct Answer: Enhance turbulence ✔

Option A: 10-50

Option B: 100-500

Option C: 1000-1500

Option D: 5000-15000

Correct Answer: 5000-15000 ✔

Option A: Wavelength of radiation

Option B: Nature of the body

Option C: Temperature of the body

Option D: None of these

Correct Answer: Temperature of the body ✔

Option A: Δt

Option B: Δt2

Option C: Δt3

Option D: √(Δt)

Correct Answer: Δt ✔

Option A: 50 -100 Kcal/hr.m2.°C

Option B: 50 -100 W/m2.°K

Option C: 50 -100 BTU/hr. ft.2°F

Option D: 1000 – 1500 BTU/hr. ft.2°F

Correct Answer: 50 -100 BTU/hr. ft.2°F ✔

Option A: Basket type

Option B: Horizontal tube

Option C: Calandria

Option D: None of these

Correct Answer: Basket type ✔

Option A: Increases

Option B: Decreases

Option C: Is not affected

Option D: May increase or decrease; depends on the feed

Correct Answer: Decreases ✔

Option A: Increases the heating area required

Option B: Reduces the economy

Option C: Both A. and B.

Option D: Decreases the heating area required

Correct Answer: C. Both A. and B. ✔

Option A: Baffle spacing & shell diameter

Option B: Tube diameter & pitch

Option C: Viscosity, density & mass velocity of shell side fluid

Option D: None of these

Correct Answer: None of these ✔