Question

Differentiate between giving examples: Lyophobic and lyophilic colloids

Answer 1

Dear Student

Lyophobic and lyophilic colloids is the classification of colloidal sols based on the nature on interaction between the dispersed phase and dispersion medium. Lyophillic colloids are solvent attracting and lyophobic colloids are solvent repelling.

Lyophilic colloids (solvent attracting)

• These are formed by simply mixing substances like gelatine, starch, rubber etc with a suitable liquid (dispersion medium)
• If the dispersion phase is separated from the dispersion medium by any method, then the sol can be reconstituted by simply mixing the two again.

• These are called reversible sols

• Quite stable and cannot be easily coagulated.

Lyophobic colloids (solvent repelling)

• These colloids are formed by substances like metals, metal sulphides. These cannot be prepared by simply mixing the the substances with dispersion medium and require special methods.

• Also called irreversible sols

• Unstable and can be easily coagulated

• These sols need stabilising agents for their preservation.

Regards