Question

1. Why is vigorous trituration required to prepare emulsions?

2. Explain the difference between creaming and coalescence.

3. Emulsions are considered to be physically and thermodynamically unstable systems. Describe an approach that can be used to enhance the stability of an emulsion.

4. Using the 4:2:1 method, what are the consequences of not adding in the water all at once during preparation of the primary emulsion?

Answer 1

Ans.1.) Trituration is required during preparation of emulsion to mix the oil and water thoroughly and properly.

2.) Creaming is the migration of the dispersed phase of an emulsion, under the influence of buoyancy. The particles float upside or sink, depending on how big they are and how much less thick or thicker they may be than the continuous phase and also how thixotropic the continuous phase might be. As long as the particles continue in a separated state, the process is called creaming. On the other hand, coalescence is the process by which two or more droplets or bubbles combine during contact to form a single droplet.

3.) Emulsion can be stabilized by increasing the repulsion between the dispersed phase i.e., by increasing the electrostatic repulsion or steric repulsion. Emulsifiers are amphiphiles that reduce the interfacial tension between the two phases and contribute to the stabilization of dispersed droplets with electrostatic or steric effects. Hence, addition of emulsifier enhances the stability of emulsion.

4.) If the water is not added at once, the resulting emulsion would be creamy white and does not produces a crunching sound as it is triturated.