Question

Which type of colloids are generally more stable?

• A. Lyophilic colloids
• B. Lyophobic colloids
• C. Both A and B
• D. We can’t generalize either Lyophilic colloids or Lyophobic as being more stable

Answer 1

The correct option is A Lyophilic colloids

When we get a colloidal system readily by warming or shaking the substance with a suitable solvent, it is called as lyophilic colloid. The term ‘lyo’ means ‘solvent’ while the term ‘philic’ implies ‘to love’. So these colloids are solvent-loving. For example, gelatin, starch, proteins, gum and rubber sols.
On the other hand, lyophobic sols are solvent-hating as the term ‘phobic’ means ‘to hate’. They are not easily obtained. Examples include gold sols, Sulphur sol, $A{s}_2{S}_3$ sol and a sol of $Fe(OH{)}_3$.
Due to extensive solvation, lyophilic colloids are much more stable than lyophobic ones. In fact, if by some means like evaporation, we separate the suspended particles of a lyophilic sol, these particles could then be reconstituted into the colloid just by adding the dispersion medium. For this reason, lyophilic sols are called reversible sols. Lyophobic sols can be precipitated rather easily and they are called irreversible sols.