A colloid is a heterogeneous mixture oftwo substances of different phases. Shaving cream and other foams are gas dispersed in liquid. Jello, toothpaste, and other gels are liquid dispersed in solid. Dough is a solid dispersed in a liquid.
Shaving cream is a special type of mixture called a colloid, consisting of tiny air bubbles dispersed in liquid. This particular type of colloid can also be classified as a foam.
