Evaporation MCQs : This section focuses on the "Evaporation". These Multiple Choice Questions (MCQs) should be practiced to improve the Evaporation skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
A major reason as to why evaporators and their selection for different applications in the food industry is very important is because ______
A. Organoleptic characteristics of food is very important
B. Many food items are heat sensitive
C. Majority of them have high moisture content
D. All of the mentioned reasons
Question 2
At a food processing industry, the steam was re-compressed and a small amount of steam at high pressures and temperatures was sent into the next evaporation chamber in a multiple effect evaporator. Which of the following is true with respect to the above sentences?
A. There might be wear and tear in the evaporator
B. The overall pressure and temperature of steam increases which is desired
C. The capacity of the evaporator increases
D. All of the mentioned
Question 3
Desolventization which is done in certain evaporators is more similar to distillation than evaporation.
A. TRUE
B. FALSE
Question 4
During evaporation of edible solutions, the BPR-boiling point rise should be _____ and the foaming and scale formation should be _____
A. Low, minimum
B. High, maximum
C. Low, maximum
D. High, minimum
Question 5
In a rising film evaporator, the temperature difference need not be as high as that in a falling film evaporator.
A. TRUE
B. FALSE
Question 6
In flashing of jams, the temperature of concentrated jam _____ on flashing. Also, the vapor pressure of the concentrated jam _____
A. Decreases, sustains combustion
B. Increases, sustains combustion
C. Decreases, does NOT sustain combustion
D. Increases, does NOT sustain combustion
Question 7
In plate evaporator, the heat transfer coefficient is high in spite of low residence time because _____
A. It deals with high viscosity food items
B. It is economic
C. Feed is made to pass as thin film
D. All of the mentioned reasons
Question 8
Industry A is low on budget and is used in the sugar industry. Industry B wants to invest in a good evaporator. They are needed for meat extracts. Which evaporators will you suggest for each of them?
A. Forced circulation evaporator, forced circulation evaporator
B. Rising film evaporator forced circulation evaporator
C. Forced circulation evaporator, rising film evaporator
D. Rising film evaporator, rising film evaporator
Question 9
Mixed feed arrangement offers the advantage of omitting the usage of pumps by transferring feed in the direction of low pressure. That's an advantage taken from forward feeding arrangement.
A. TRUE
B. FALSE
Question 10
One disadvantage with backward feeding is that the feed gets very concentrated at the beginning few units itself and hence it's difficult to feed it to the next evaporator unit.
A. TRUE
B. FALSE
Question 11
Which of the following is true while concentrating jams?
A. They're sensitive to heat
B. Evaporation process for jams is carried out under vacuum
C. At vacuum, the boiling point decreases
D. All of the mentioned
Question 12
_________ wastes can be treated in evaporator.
A. Aqueous inorganic
B. Organic
C. Aqueous organic
D. Dry
Question 13
__________ separation techniques are used before evaporation process.
A. Physical
B. Chemical
C. Biological
D. Biochemical
Question 14
Evaporation of liquids from hazardous waste through multiple evaporator, distillation etc. is dependent on ________
A. Melting point
B. Freezing point
C. Boiling point
D. Vapour pressure
Question 15
Evaporation units may be operated without obtaining a permit if ________
A. Chemicals are used
B. Resins are associated
C. Unit is enclosed
D. Waste is reused
Question 16
Evaporator must have sufficient disc engaging space to achieve ________
A. Separation
B. Chemicals
C. Boiling
D. Pressure
Question 17
Liquids with high vapour pressure evaporates slowly.
A. True
B. False
Question 18
Rate of evaporation of liquid waste is measured by _______
A. Vapour pressure
B. Pressure
C. Temperature
D. Heat
Question 19
The residues produced from evaporation treatment is _________
A. Less
B. More
C. Undetermined
D. No residue
Question 20
Which of the following waste is not applicable for evaporation?
A. Calcium
B. Iron
C. Copper
D. Methylene chloride
Question 21
Which of the following is not an assumption in the evaporator model?
A. The feed has only one volatile components
B. Only the latent heat of vaporization is available for heating the solution
C. Boiling action in heat exchanger ensures perfect mixing
D. Overall temperature driving force is the temperature that of saturated steam
Question 22
Which of the following is a characteristic of a horizontal tube evaporator?
A. Agitation is provided only by bubbles leaving the evaporator as vapor
B. The tube bundle is arranged vertically, with the solution inside the tubes condensing outside
C. To handle viscous solution a pump is used to force liquid upwards
D. Also called short vertical tube evaporator