Question

How does surface tension varies according to lyophobic and lyophilic colloids and pls explain me the reason why does surface tension varies that way

Answer 1

Lyophilic: The surface tension of these sols is less than that of dispersion medium.

Lyophobic: The surface tension is nearly same as that of dispersion medium.

The substances which when mixed with a suitable liquid (dispersion medium) readily form colloidal solutions are called lyophilic colloids. They are heavily hydrated due to which there is increase in viscosity and decrease in surface tension than the dispersion medium.

The substances which do not possess affinity for the dispersion medium and do not readily pass into the sol state when mixed with the medium are called Lyophobic colloids. They are not much hydrated and there is much less interaction with dispersion medium due to which their viscosity and surface tension are same as that of dispersion medium.