Solutions vs. Suspensions

Attribute	Solutions	Suspensions
Homogeneity	Homogeneous mixture	Heterogeneous mixture
Particle size	Particles are dissolved and not visible	Particles are visible and not dissolved
Stability	Stable over time	May settle over time
Separation	Does not separate upon standing	May separate upon standing
Filterability	Cannot be filtered	Can be filtered

Definition

A solution is a homogeneous mixture composed of two or more substances. In a solution, the solute is evenly distributed throughout the solvent. This results in a clear and transparent mixture. On the other hand, a suspension is a heterogeneous mixture in which particles are dispersed throughout a liquid or gas, but are large enough to settle out over time. Suspensions are typically cloudy or opaque due to the presence of these visible particles.

Particle Size

One of the key differences between solutions and suspensions is the size of the particles involved. In a solution, the particles of the solute are typically very small, often at the molecular or ionic level. These particles are so tiny that they do not scatter light, which is why solutions are clear. In contrast, the particles in a suspension are much larger and can be seen with the naked eye. These larger particles scatter light, giving suspensions their cloudy appearance.

Stability

Solutions are generally stable and do not separate over time. The solute particles are evenly distributed and do not settle out of the solvent. This makes solutions ideal for many applications where a uniform mixture is desired. On the other hand, suspensions are not stable and will eventually separate. The larger particles in a suspension will settle to the bottom of the container if left undisturbed. This is why suspensions must be shaken or stirred before use to redistribute the particles.

Clarity

As mentioned earlier, solutions are clear and transparent due to the small size of the solute particles. This clarity makes solutions ideal for applications where a clear liquid is needed, such as in pharmaceuticals or food products. Suspensions, on the other hand, are cloudy or opaque because of the larger particles dispersed throughout the mixture. This lack of clarity can be a disadvantage in certain applications where a clear liquid is required.

Separation

Separating the components of a solution is typically more difficult than separating the components of a suspension. In a solution, the solute particles are dissolved in the solvent at a molecular level, making them difficult to separate by physical means. Separating a suspension, on the other hand, is relatively easy. The larger particles in a suspension can be filtered out or allowed to settle and then decanted off. This makes suspensions easier to work with in some cases.

Examples

Common examples of solutions include saltwater, sugar water, and air (a mixture of gases). These solutions are clear and homogeneous, with the solute particles evenly distributed throughout the solvent. In contrast, examples of suspensions include muddy water, Italian dressing, and paint. These mixtures are cloudy or opaque due to the presence of visible particles that do not dissolve in the solvent.

Applications

Solutions and suspensions have different applications based on their properties. Solutions are often used in industries such as pharmaceuticals, food and beverage, and cleaning products. The uniformity of solutions makes them ideal for these applications. Suspensions, on the other hand, are used in products such as paints, cosmetics, and some medications. The ability of suspensions to hold particles in suspension allows for unique formulations in these industries.