An emulsion is a type of colloidal system in which both the dispersed phase and the dispersion medium are liquids that normally do not mix with each other. One liquid is finely divided into tiny droplets and distributed throughout another liquid.
- Since the two liquids are immiscible (do not dissolve in each other), an emulsifying agent (like soap, detergent, or egg yolk) is often added to stabilize the emulsion and prevent the droplets from separating.
- Emulsions are usually opaque or milky in appearance because light scatters off the tiny droplets.
Types of Emulsions:
- Oil-in-Water (O/W) Emulsion: Oil droplets dispersed in water.
- Examples: Milk, cream, ice cream.
- Water-in-Oil (W/O) Emulsion: Water droplets dispersed in oil.
- Examples: Butter, margarine, cold creams.
Examples of Emulsions in daily life:
- Milk (oil-in-water).
- Mayonnaise (oil-in-water with egg yolk as emulsifier).
- Butter (water-in-oil).
- Lotions and cold creams (cosmetics).
- Paints and inks (industrial emulsions).
In short, an emulsion is a mixture of two immiscible liquids where one liquid is dispersed as droplets in another, often stabilized by an emulsifier.