Question

Surface tension of lyophilic sols is:

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• A. None of these
• B. Equal to water
• C. More than water
• D. Lower than water

Answer 1

The correct option is D Lower than water

When a collide is attracted towards water molecules that means they are Lyophilic (Lyo means solvent and philic means loving). When these colloids are mixed with the favorable liquid, a high force of attraction exists between liquids and colloidal particles that end with the formation of a very stable solution called lyophilic sol.
The surface tension of lyophilic sols is lower compared to the surface tension of water because the lyophilic colloids have a great affinity (attraction) towards the water solvent which decreases the surface tension.
In lyophilic sols particles are heavily hydrated due to which there is an increase in viscosity and increase in viscosity decreases the surface tension.
Hence the correct answer is (a).