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Question
Explain the term emulsion and types of emulsions.
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Solution
- A colloidal system in which one liquid is dispersed in another immiscible liquid is called an emulsion.
- There are liquid-liquid colloidal systems in which both liquids are either completely or partially immiscible.
- There are two types of emulsions:
- Emulsion of oil in water (o/w type):
An emulsion in which a dispersed phase is oil and the dispersion medium is water is called emulsion of oil in water.
Example:
1. Milk consists of particles of fat dispersed in water.
2. Other examples include vanishing cream, paint, etc. - Emulsion of water in oil (w/o type):
An emulsion in which the dispersed phase is water and dispersion medium is the oil is called emulsion of water in oil.
Example:
1. Cod liver oil consists of particles of water dispersed in oil.
2. Some other examples of this type include butter, cream, etc.
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