Solution Definition in Chemistry

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A solution is a homogeneous mixture of two or more substances. A solution may exist in any phase.

A solution consists of a solute and a solvent. The solute is the substance that is dissolved in the solvent. The amount of solute that can be dissolved in solvent is called its solubility. For example, in a saline solution, salt is the solute dissolved in water as the solvent.

For solutions with components in the same phase, the substances present in lower concentration are solutes, while the substance present in highest abundance is the solvent. Using air as an example, oxygen and carbon dioxide gases are solutes, while nitrogen gas is the solvent.

Note that whether or not components start in different phases, a solution only consists of one phase. For example, sugar is a solid, while water is a liquid, However, a solution of sugar water is liquid only.

Characteristics of a Solution

A chemical solution exhibits several properties:

  • A solution consists of a homogeneous mixture.
  • A solution is composed of one phase (e.g., solid, liquid, gas).
  • Particles in a solution are not visible to the naked eye.
  • A solution does not scatter a light beam.
  • Components of a solution cannot be separated using simple mechanical filtration.

Solution Examples

Any two substances which can be evenly mixed may form a solution. Even though materials of different phases may combine to form a solution, the end result always exists of a single phase.

An example of a solid solution is brass. An example of a liquid solution is aqueous hydrochloric acid (HCl in water). An example of a gaseous solution is air.

Solution Type Example
gas-gas air
gas-liquid carbon dioxide in soda
gas-solid hydrogen gas in palladium metal
liquid-liquid gasoline
solid-liquid sugar in water
liquid-solid mercury dental amalgam
solid-solid sterling silver
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Your Citation
Helmenstine, Anne Marie, Ph.D. "Solution Definition in Chemistry." ThoughtCo, Oct. 24, 2022, Helmenstine, Anne Marie, Ph.D. (2022, October 24). Solution Definition in Chemistry. Retrieved from Helmenstine, Anne Marie, Ph.D. "Solution Definition in Chemistry." ThoughtCo. (accessed May 28, 2023).