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Surface Chemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistrySurface Chemistry3 Marks
Question
Describe the following types of colloids, giving an example for each:
  1. Multimolecular colloids.
  2. Macromolecular colloids.
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Answer

  1. Multimolecular colloids: When a large number of atoms or smaller molecules of a substance aggregate together to form species having size (with diameters less than 1nm) in the colloidal range are called multimolecular colloids. e.g. a gold sol, sulphur sol.
  2. Macromolecular colloids: When the size of the macromolecules may be in the colloidal range such systems are called macromolecular colloids. e.g. starch, cellulose, proteins, enzymes.

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