Engineering Questions with Answers - Multiple Choice Questions
Separation Processes MCQ’s – Basic separation Techniques
1 - Question
Which of the following separation techniques is dependent on difference in volatility?
c) Magnetic separation
d) Fractional crystallization
Explanation: Distillation process is dependent on difference in volatility. Example:- Vapor pressure, Boiling point
2 - Question
Crystallization exploits difference in which factors?
a) Specific heat
b) Boiling point
c) Melting point
d) Bubble point
Explanation: The difference in melting point in case of crystallization leads to the separation of the mixture.
3 - Question
What is the separation by polymer membrane?
a) Exploits the difference in volatility
b) Exploits the difference in diffusivity
c) Exploits the difference in flowability
d) Exploits the difference in permeability
Explanation: In a polymer membrane, only the substances which are suitable to the membrane are passed and the rest do not pass.It can be based on the pore size of the membrane.
4 - Question
Which of the following separation techniques exploits differences in electric charge and diffusivity?
d) Liquid Chromatography
Explanation: Electrophoresis is based on the difference in the electrical charges and their diffusivity. Based on the difference in diffusivity of electrical charges, the components are separated
5 - Question
What is the size of equipment determined by?
a) Rate of mass transfer from one phase to another
b) Rate of heat transfer from one phase to another
c) The number of reactions taking place
d) The amount of byproduct formed
Explanation: The amount of the feed i.e. the amount of mass transferred from one part of the separation process to another will determine the equipment size. More the mass transfer, larger shall be the equipment.
6 - Question
Which of the following is not an important property that governs the extent of separation?
b) Vapor pressure
d) Radius of gyration
Explanation: The temperature of the feed will decide the state of the feed and in turn will decide the separation technique to be used. However it will have no effect on extent of separation.
7 - Question
Which of the following methods are to be applied to separate Oxygen rich components and Nitrogen rich components?
b) Zone melting
c) Magnetic separation
Explanation: The difference between the boiling point of oxygen (-183oC) and Nitrogen (-195.8oC) is frequently large to be separated by distillation.
8 - Question
How will you separate o-Xylene and m-Xylene products of the same compounds?
c) Polymer membrane
Explanation: The above mentioned components have same boiling points. So distillation cannot be used. Since they have a difference in melting point, crystallization is used.
9 - Question
How is Oil and Hexane separated?
b) Separating funnel
Explanation: Oil and Hexane will have huge differences in the molecular weights. Hence they will form two phases in a separating funnel. Thus the layer that settles down can be removed. Distillation cannot be used here because oil might get damaged.
10 - Question
How a mixture of isopropyl alcohol and water is be separated?
a) One step distillation
b) Two step distillation
c) Two step crystallization
d) Separating funnel
Explanation: A two-step distillation is employed where there is an addition of benzene which is soluble in IPA and thus forms a layer. Now IPA and benzene mixture can be separated from water using a separating funnel. Further distilling, we get benzene and IPA.
11 - Question
How a mixture of iron and copper fillings is be separated?
a) Magnetic separation
Explanation: Magnetic separation is employed since the components have difference in magnetic properties.
12 - Question
How can the DNA fragments be separated from DNA?
d) Zone melting
Explanation: DNA fragments migrate to positive electrode in the electric field.