Chemistry · Science General

Separation Techniques

842 Questions

Separation techniques involve physical methods to isolate mixtures, including distillation, filtration, and crystallization. Competitive exams frequently test these foundational concepts. Review the exact processes to enhance problem solving speed.

Distillation and evaporationCrystallization processFiltration methodsSeparating dissolved solidsChromatography and mass techniques

Separation Techniques Questions

Multiple choice

Which two types of impurities are separated by sand removal tank?

  1. Rays and tissue papers

  2. Pebbles and sand

  3. Detergents and grass pieces

  4. Oil and grease
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sand removal tanks are designed to trap heavy, settleable inorganic solids through sedimentation. Pebbles and sand particles settle to the bottom due to their weight, while lighter materials like oils, grease, and organic debris remain suspended or float for later removal stages.

Multiple choice

Isoelectric focussing technique that is used to separate proteins works on the principle of

  1. electrophoretic separation based on relative content of acidic and basic residues

  2. mass of the protein molecules

  3. number of amino acids containing sulphur

  4. coagulation capacity of the protein molecules

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Isoelectric focussing (IEF) is an electrophoretic method that separates proteins according to their isoeletric points(pI). proteins carry both positive and negative charges and their net charge depends highly on the pH of their surroundings. the pI is the specific pH at which the net charge on a protein molecule is zero. Thus, Isoelectric focussing technique used to separate proteins works on the principle of electrophoretic separation based on relative content of acidic and basic residues.

Multiple choice

Ion exchange chromatography is applicable for the separation of molecules on the basis of their charge. It is based on the reversible exchange ions in the solution with the ions bound to supportive media.

If you want to separate a positively charged protein using ion exchange chromatography, what kind of chromatography will be suitable?

  1. Anion exchange chromatography

  2. Cation exchange chromatography

  3. Both 1 and 2

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

To separate a positively charged protein, we should use a negatively charged resin. For example, commonly we use the resin Phosphocellulose, which is a negatively charged resin for the cation exchange chromatography.

Multiple choice

Alcohol and water are easily separated by distillation because of their

  1. different boiling points

  2. different colours

  3. different densities

  4. all of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Alcohol and water are easily separated by distillation because of their different boiling points. Moreover, distillation is used to separate a mixture of two liquids having different boiling points.

Multiple choice

Sodium chloride can be separated from sand by first adding water to the mixture to dissolve the sodium chloride. The separation then takes place in two stages, which are

  1. filtration followed by decantation

  2. distillation followed by decantation

  3. filtration followed by evaporation

  4. evaporation followed by filtration
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Firstly, sand is separated from the mixture by filtration. Then, by evaporation, water gets evaporated and sodium chloride is left behind.

Multiple choice

A chalk which is settled at the bottom of a beaker filled with water can be separated from the water by ________ and __. The chalk can then be dried by ___. (a) sedimentation and crystallisation; condensation (b) decantation and filtration, evaporation (c) filtration and evaporation; crystallisation

  1. Only (a)

  2. Only (b)

  3. Only (b) and (c)

  4. Only (c)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Some chalk powder settled at the bottom of a beaker filled with water can be separated from water by decantation and filtration. The chalk powder can then be dried out by evaporation. 

Multiple choice

Which of the following liquid - liquid mixtures cannot be separated by a separating funnel?

  1. Benzene and water
  2. Kerosene oil and water
  3. Ethyl alcohol and water
  4. Acetone and ethyl alcohol

  1. 1 and 2

  2. 3 and 4

  3. 1 and 3

  4. 2 and 4
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Separating funnel is used to separate a mixture of immiscible liquids. Only the mixtures in options 1 and 2 can be separated by using a separating funnel as they are mixtures of immiscible liquids. The mixtures in options 3 and 4 cannot be separated by a separating funnel because they are mixtures of miscible liquids.

Multiple choice

Consider the information given below about methods of separation, types of mixtures and nature of mixtures. Which of the following is/are incorrectly matched?

     
S. No. Method Type of mixture Nature of mixture
1. Magnetic separation Solid-Solid Heterogeneous
2. Fractional distillation Liquid-Solid Heterogeneous
3. Separating funnel Liquid-Liquid Heterogeneous
4. Filtration Liquid-Liquid Heterogeneous

  1. Only 1

  2. Both 2 and 3

  3. Both 2 and 4

  4. Only 2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fractional distillation is used to separate miscible liquids having different boiling points. Filtration is used to separate a heterogeneous mixture of solid and liquid.

Multiple choice

Different properties of three processes P, Q and R are given in the table below. Identify the processes by choosing the correct code from the given alternatives.

 
Processes Properties
P Used to separate suspended particles from water
Q Used to separate immiscible liquids
R Used to separate a mixture of NaCl and water

  1. P – Filtration, Q – Separating funnel, R – Distillation

  2. P – Distillation, Q – Filtration, R – Separating funnel

  3. P – Sedimentation, Q – Filtration, R – Chromatography

  4. P – Sublimation, Q – Separating funnel, R – Distillation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

P - It is filtration method which is used to separate suspended particles from water. Q - A separating funnel is used in liquid-liquid extractions to separate (partition) the components of a mixture into two immiscible solvent phases of different densities. R - It is distillation method which is used to separate a mixture of NaCl and water.