Crystallization MCQs : This section focuses on the "Crystallization". These Multiple Choice Questions (MCQs) should be practiced to improve the Crystallization skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
Advantage of Draft tube baffles crystallizer _____
A. Re-circulation of a small fraction of mother liquor
B. Selectively separates big particles from the smaller ones
C. All of the mentioned
D. None of the mentioned
Question 2
Automated valves should be avoided.
A. TRUE
B. FALSE
Question 3
Celinium Sulphate is an exception of the solubility curve. When the temperature is increased, its solubility decreases.
A. TRUE
B. FALSE
Question 4
Draft tubes _____ crystal-crystal attrition. Crystals _____ bottom.
A. Increase, should be kept on
B. Increase, should be kept off
C. Decrease, should be kept on
D. Decrease, should be kept off
Question 5
Excess nucleation leads to _____
A. Non-uniform CSD
B. In huge capacity vessels, the crystal-crystal attrition leads to formation of small size particles hence no crystallization
C. Non-uniform CSD, in huge capacity vessels, the crystal-crystal attrition leads to formation of small size particles hence no crystallization
D. None of the mentioned
Question 6
Heating on the surface of a heat exchanger leads to fouling.
A. TRUE
B. FALSE
Question 7
High residence time encourages _____
A. Attrition
B. Crystal growth
C. Attrition & Crystal growth
D. None of the mentioned
Question 8
In making of cocoa butter via crystallization, liquid is the desired product.
A. TRUE
B. FALSE
Question 9
Incrustation leads to _____
A. Affects safety
B. Damages equipment
C. Affects product quality
D. All of the mentioned
Question 10
Parameters affecting crystallization are ____________
A. Agitator speed
B. Population density
C. Purity of solution
D. All of the mentioned
Question 11
Scraped surface crystallizers can be used for viscous fluids up to 10000 cp.
A. TRUE
B. FALSE
Question 12
Secondary nucleation involves the collision of crystals.
A. TRUE
B. FALSE
Question 13
The ratio of concentration of a super saturated solution to a saturated solution is denoted by α' which is stated by the Kelvin equation. How is it related to the crystal size and interfacial tension between solid and liquid?
A. Directly, indirectly
B. Indirectly, directly
C. Directly, directly
D. Indirectly, indirectly
Question 14
What does excess supersaturating followed by cooling lead to?
A. Primary nucleation
B. Secondary nucleation
C. Both, nucleation and crystal growth in general
D. None of the mentioned
Question 15
Which of the following facilitates crystallization?
A. Hot concentrated solution is cooled for crystals to form
B. Solution is concentrated by evaporation
C. Adiabatic evaporation and cooling
D. All of the mentioned
Question 16
Which of the following is NOT an important criteria for crystal formation?
A. Caking characteristics of the crystal
B. Moisture content
C. Shape
D. None of the mentioned
Question 17
Which of the following is true about scraped surface crystallizers?
A. Expansion of capacity is easy
B. Can be used for a wide range of temperature differences
C. Smaller size, less installation cost
D. All of the mentioned
Question 18
Which of the following needs to be taken care of during scale up of crystallizers?
A. Reynolds number
B. Residence time
C. Power supplied to agitator per unit volume
D. All of the mentioned
Question 19
Which of the following tells the significance of crystallization in food processing?
A. Consistency of food emulsions
B. A good feel of food inside the mouth
C. The physical stability of food
D. All of the mentioned
Question 20
Work of Draft tube in Draft tube baffle crystallizer is _____
A. Maintaining good circulation rate for slurry
B. Reducing energy requirement for mixing
C. Maintaining good circulation rate for slurry & reducing energy requirement for mixing
D. None of the mentioned