Test: Emulsions (Old NCERT) - NEET MCQ

Butter is an example of water in oil type emulision.

Emulsifying Agents:
An emulsifying agent is a substance that helps to stabilize and disperse two immiscible substances, such as oil and water, into a stable and homogeneous emulsion. Emulsifying agents can be classified into various categories, including proteins, gums, soaps, and electrolytes.
Options:
Let's analyze each option to identify the one that is not an example of an emulsifying agent:
A. Proteins: Proteins are commonly used as emulsifying agents in food and cosmetic products. They have the ability to form stable emulsions by reducing the surface tension between oil and water. Therefore, proteins can be considered as emulsifying agents.
B. Gums: Gums, such as xanthan gum and guar gum, are frequently used as emulsifying agents in food products. These gums have a high viscosity and can stabilize oil-in-water emulsions by forming a protective layer around the dispersed oil droplets.
C. Soaps: Soaps are surfactants that can act as emulsifying agents. They have a hydrophilic (water-loving) head and a hydrophobic (oil-loving) tail, allowing them to interact with both oil and water. Soaps can form micelles, which help to disperse and stabilize oil droplets in water.
D. Electrolytes: Electrolytes, such as salts, are not commonly used as emulsifying agents. They do not possess the necessary properties to stabilize and disperse immiscible substances. Therefore, electrolytes are not an example of an emulsifying agent.
Conclusion:
From the given options, the correct answer is D: Electrolytes. Electrolytes are not considered as emulsifying agents because they do not possess the necessary properties to stabilize and disperse immiscible substances.

The separation of an emulsion into its constituents is called demulsification. Various methods of demulsification are freezing, boiling, centrifugation or chemical methods.

Emulsions can be diluted with any amount of the dispersion medium. On the other hand, the dispersed liquid when mixed, forms a separate layer.