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Surface Chemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistrySurface Chemistry3 Marks
Question
What is the difference between multi molecular and macromolecular colloids? Give one example of each type. How are associated colloids different from these two types of colloids?
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Answer

Multimolecular colloids Macromolecular colloids
They are aggregates of molecules less than 1nm thick.
Example: Sulphur Sol.		 They themselves are large molecules of colloidal dimensions.
Example: Starch.
Associated colloids – are those which at low concentration behave as normal electrolytes & at high concentration act as colloids.

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