The substances thus added to stabilise the emulsions are called emulsifiers or emulsifying agents.
The substances commonly used as emulsifying agents are soaps of various kinds, long chain sulphonic acids `(i.e.,` detergents `)` or lyophilic `(` proteings, gums , agar etc `.` ltbr. Role of amulsifier `:`
Sopa consists of two parts, the hydrocaron part `(C_(15)H_(31),C_(17)H_(35),` etc `)`. which is soluble in oil and the polar group `(COO^(c-)Na^(o+))` which is soluble in water.
When a drop of oil is added to the soap part, the `R-` part of the soap remains in the oil and `COO^(c-) Na^(c-)` part remains in water. THus, soap molecules are concentrated over the surface of drop of oil. As a result, the interfacial between oil and water decreses & hence they are intermixed into each other to form the emulsion to form micells.
