Which diagram best represents a liquid–liquid emulsion such as milk? The colored balls represent different liquid molecules. [Section 13.6]

Key Concepts

Emulsions

An emulsion is a mixture of two immiscible liquids where one liquid contains a dispersion of the other. In the case of milk, it is an emulsion of fat droplets dispersed in water. Emulsions are stabilized by emulsifiers, which reduce the surface tension between the two liquids, allowing them to mix more uniformly.

Molecular Representation

Molecular representation involves using symbols or diagrams to illustrate the arrangement and interaction of molecules in a substance. In the context of emulsions, colored balls can represent different types of molecules, helping to visualize how the dispersed phase (like fat) interacts with the continuous phase (like water) in the emulsion.

Phase Separation

Phase separation occurs when two immiscible liquids do not mix and instead form distinct layers. In emulsions, this separation can be minimized through the use of emulsifiers, but if left undisturbed, the dispersed droplets may coalesce and rise or settle, leading to a separation of phases. Understanding this concept is crucial for analyzing the stability of emulsions like milk.