Question

defination of emulsion , defination of foam and defination of gel

Answer 1

An emulsion is a colloid in which minute droplets of one liquid is dispersed in another liquid which is not miscible with it
The foam is a colloid in which a gas is dispersed in a liquid medium
The gel is a semi solid colloid in which there is a continuous network of solid particles dispersed in a liquid

Answer 2

foam:- a mass of small bubbles formed on or in liquid
gel:- a thick clear and sticky substance used in cosmetics or in medicines