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Video Example : Methods of Separation

Methods of Separation


  • Evaporation
  • Centrifugation
  • Sublimation
  • Separating funnel
  • Filtration

Definition of Methods of Separation

A method of separation, is any mass transfer process that contain a mixture of substances into two or more distinct product mixtures, at least one of which is enriched in one or more of the mixture's constituents

More About Methods of Separation

  • In some cases, a separation may fully divide the mixture into its pure constituents
  • Separations are carried out based on differences in chemical properties, or physical properties such as size, shape, mass, density, or chemical affinity between the constituents of a mixture, and are often classified according to the particular differences they use to achieve separation
  • In the case that no single difference can be used to accomplish a desired separation, multiple processes will often be performed in combination to achieve the desired end
  • Separation makes it possible to study the properties of each individual component separately and use it
  • Heterogeneous mixtures can be separated by simple physical processes such as hand picking, sieving, filtration
    • I) Evaporation: Evaporation is the process of vaporizing the solvent to obtain the solute
      We can separate salt from a solution by evaporating the water from the solution
      Ink, which is a mixture of dye and water, can be separated by evaporation
      By heating ink indirectly on a lid of a hot water beaker, water in the ink gets evaporated and we get the dye
      ii) Centrifugation: You can separate the mixtures of solids and liquids such as fat in the cream by the process of centrifugation
      Cream can be separated from full cream milk by using the method of centrifugation
      When the solid particles are very small and pass through filter paper, they are separated from the liquid by centrifugal machine. In the laboratory, precipitates are separated from the liquids by centrifugation
      iii) Separating funnel: When two immiscible liquids are mixed up, they are separated by using a separating funnel. The principle is that immiscible liquids separate out in layers depending on their densities
  • Handpicking allows the good grains to be separated from the waste and impurities
  • Sieving is a method of separating substances that are of different sizes. For example, wheat flour has some fine powdered wheat as well as some bigger impurities. When it is put through a sieve, the fine powder falls through the small holes in the sieve, while the thicker impurities remain as they are too big to pass through these holes
  • Filtration is a process by which insoluble solids can be removed from a liquid by using a filter paper
  • In the filtration process:
  • liquid that filters through is the filtrate
  • undissolved solid particles are residue
  • Salt and a sublimable solid such as ammonium chloride, can be separated by the process of sublimation.
  • Solids like camphor, naphthalene and anthracene are examples of solids that sublimate