Practicing Success
Emulsion: These are liquid-liquid colloidal systems, i.e., the dispersion of finely divided droplets in another liquid. If a mixture of two immiscible or partially miscible liquids is shaken, a coarse dispersion of one liquid in the other is obtained which is called emulsion. Generally, one of the two liquids is water. There are two types of emulsions. (i) Oil dispersed in water (O/W type) and (ii) Water dispersed in oil (W/O type).
Emulsions of oil in water are unstable and sometimes they separate into two layers on standing. For stabilisation of an emulsion, a third component called emulsifying agent is usually added. The emulsifying agent forms an interfacial film between suspended particles and the medium. The principal emulsifying agents for O/W emulsions are proteins, gums, natural and synthetic soaps, etc., and for W/O, heavy metal salts of fatty acids, long chain alcohols, lampblack, etc. |
Which of the following is not a method to test the type of emulsion? |
Microscopic method Conductance method Coagulation method Dye method |
Coagulation method |
The process of aggregating colloidal particles to create larger-sized particles, which eventually settle as a precipitate, is known as coagulation or precipitation. The diverse emulsion testing techniques include the conductance, microscopic, and dye procedures. |