What term describes a mixture that must be shaken or mixed well before use?

The term that describes a mixture that must be shaken or mixed well before use is a suspension. Suspensions consist of solid particles that are dispersed throughout a liquid but do not dissolve. Over time, these solid particles can settle at the bottom of the container, which is why mixing is necessary to ensure an even distribution of the particles throughout the liquid. This characteristic differentiates suspensions from solutions, where the solute fully dissolves in the solvent, and from emulsions, where two immiscible liquids are combined with the help of an emulsifying agent. A general mixture, on the other hand, does not necessarily require mixing before use, as it can be a broader categorization of substances that may include solutions, suspensions, and emulsions.

Thus, understanding that suspensions need to be mixed to ensure they are homogeneous is vital for proper application, especially in beauty and wellness products.