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

What is the method used to separate cream from milk?

  1. Filtration

  2. Centrifugation

  3. Crystallisation

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

Centrifugation uses centrifugal force to separate substances of different densities. Cream (fat) is less dense than skim milk, so it rises to the top and can be separated by spinning. Filtration separates solids from liquids using a filter. Crystallisation purifies dissolved solids from a solution.

Multiple choice

Release of CFCs is also known as

  1. freon

  2. depletion

  3. contanination

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

A chlorofluorocarbon (CFC) is an organic compound that contains only carbon, chlorine, and fluorine, produced as volatile derivative of methane, ethane, and propane. They are also commonly known by the DuPont brand name Freon. The most common representative is dichlorodifluoromethane (R-12 or Freon-12).

Multiple choice

Micromanipulator is used for the isolation of microorganism in

  1. streak plate method

  2. pour plate method

  3. enrichment culture technique

  4. single cell isolation technique

  5. serial dilution technique
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Micromanipulator is used in single cell isolation technique for the isolation of microorganisms in pure culture. It is an equipment used to pick up a single cell and transferr to suitable medium.

Multiple choice

Which of the following is not a method of isolation of microbes?

  1. Pour plate method

  2. Streak plate method

  3. Serial dilution method

  4. Sterilisation method

  5. Enrichment culture technique
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sterilization method is not a isolation method of microbes. A steam temperature of 121oC is usually maintained for wet sterilization in autoclave at pressure 15 lbs/inch2 (1.05 kg/sq.cm). Fifteen minutes of duration is sufficient for sterilization. Culture media are wet sterilized because they are either liquid or semi-solid gels containing water.

Multiple choice

Which of the following is not an application of centrifugation?

  1. For separating textiles.

  2. Removing fat from milk to produce skimmed milk.

  3. Separating different grades of plastic.

  4. Separation of urine components and blood components in forensic lab.

  5. Separation of water particles from clothes while spin drying in washing machine.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The method used is gravity separation.

Multiple choice

In which of the following situations is sieving used?

  1. Used for the separation of slightly larger sized impurities.

  2. Used to separate heavier and lighter components of a mixture.

  3. Used when components of a mixture have different sizes.

  4. Used to separate two immiscible liquids.

  5. Used to remove tiny particles from liquids.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The method used is sieving.

Multiple choice

Which of the following statements is true?

  1. A mixture of lemon juice and water can be separated by filtration.

  2. Sugar can be separated from tea by the process of filtration.

  3. Seeds of paddy are separated from stalks by the process of winnowing.

  4. A mixture of ethanol and water can be separated by fractional distilation.

  5. Sand from water can be separated by sieving.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fractional distilation is used to separate two miscible liquids.

Multiple choice

Which of the following methods is used to separate the coloured components of a mixture?

  1. Crystallisation

  2. Chromatography

  3. Evaporation

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

Chromatography is a technique for the separation of mixtures. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase. The various constituents of the mixture travel at different speeds, causing them to separate. The separation is based on differential partitioning between the mobile and stationary phases. Subtle differences in partition coefficient of a compound result in differential retention on the stationary phase and thus, change in the separation.

Multiple choice

Ammonium chloride can be separated from a mixture by

  1. evaporation

  2. distillation

  3. sublimation

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

Sublimation is the process of transition of a substance from solid phase to gas phase. Therefore, we can separate ammonium chloride from a mixture by using sublimation.