Question

Explain in detail what is hydrophilic colloid. Why are they called reversible sol?

Answer 1

Hydrophilic Colloids

A hydrophilic colloid, or hydrocolloid, is defined as a colloid system in which the colloid particles are hydrophilic polymers dispersed in water. Hydrocolloids can be either reversible or irreversible (single-state). For example, agar is a reversible hydrocolloid of seaweed extract; it can exist in a gel or liquid state and can alternate between states with either heating or cooling.

Many hydrocolloids are derived from natural sources. For example, gelatin is produced by hydrolysis of proteins from cows and fish, and pectin is extracted from citrus peel and apple pomace. Hydrocolloid-based medical dressings are used for skin and wound treatment.

hydrophhollic are water loving on evaporation these sols from jelly are like solid which again disperse to from sol on addition of water therefore these sols are called reversible sols