Suspension
Definition and meaning of Suspension in chemistry.
A suspension is a heterogeneous mixture in which solid particles are dispersed throughout a liquid (or gas) but do not dissolve. The particles are large enough to eventually settle out due to gravity.
In more detail
Suspensions differ fundamentally from solutions because the particles remain visible and distinct from the liquid phase rather than dissolving into it. The suspended solid particles are typically larger than 1 micrometer, making them visible under a microscope or to the naked eye, and causing the mixture to appear opaque or cloudy. Because gravity acts on these relatively large particles, a suspension will eventually separate if left undisturbed, with the solid settling to the bottom. Suspensions can be separated using simple physical methods like filtration or centrifugation.
Key facts
| Field | General Chemistry |
|---|---|
| Type | Heterogeneous mixture |
| Particle size | >1 micrometer (typically) |
| Separation method | Filtration or centrifugation |
When you mix sand with water, the sand particles remain suspended in the water but do not dissolve. Over time, the sand settles to the bottom, and the mixture can be separated by pouring the water through a filter.
Frequently asked questions
How is a suspension different from a solution?
In a solution, the solute dissolves completely to form a homogeneous mixture. In a suspension, solid particles do not dissolve and remain visible, creating a heterogeneous mixture that will eventually settle out.
How is a suspension different from a colloid?
Both are heterogeneous mixtures, but suspensions have larger particles (>1 micrometer) that visibly settle over time, while colloid particles (1-1000 nanometers) remain dispersed for extended periods and do not settle readily.