A solution is a homogeneous mixture made up of two or more pure substances that do not react chemically with each other. The distinction between solute and solvent is somewhat arbitrary, but generally the solute is taken as the component that is in the least amount and the solvent as the component that is in the greater amount in the solution. What is a dissolution.
When a solution is formed, the solute (minority) becomes part of the solvent (majority) in the solution, thus modifying the physical properties of each pure component separately, such as the boiling or freezing point, but without altering the chemical properties each.
The result obtained, in fact, depends to a great extent on the concentration of solute and especially on its solubility coefficient (necessary amount of a substance to saturate a certain amount of solvent) in the solvent (some substances dissolve better in others).
Solutions are classified according to the state of aggregation of their components, in:
When the solute and solvent are solid. Solid-in-solid solutions. Alloys are an example of this type of dissolution.
When the solute is a solid and the solvent is a liquid. Solid-in-liquid solutions. They are probably the most widely used in all branches of chemistry and other areas. For example: a solution of water with salt.
When the solute is a solid and the solvent is a gas. Solid in gas solutions. For example: the dust dissolved in the air.
When the solute is a liquid and the solvent is a solid. Solutions of liquid in solid. For example: amalgams are a solution of liquid mercury and solid silver, or mercury and other metals.
When the solute is a liquid and the solvent is a liquid. Liquid-in-liquid solutions. They are also widely used in all areas of chemistry, medicine and
When the solute is a liquid and the solvent is a gas. Solutions of liquid in gas. For example: air or some other humid gas.
When the solute is a gas and the solvent is a solid. Dissolution of a gas in a solid. For example: dissolution of hydrogen in some metals.
When the solute is a gas and the solvent is a liquid. Dissolution of a gas in liquid. For example: oxygen dissolved in water, which allows fish to breathe.
Must Read: What is a comparison?
When the solute is a gas and the solvent is a gas. Dissolution of a gas in gas. For example: natural gas is a gaseous solution of methane, ethane, propane, butane, carbon dioxide and other gases in small proportions.
Dissolution and solution
For all practical purposes, the terms dissolution and solution are synonymous. Both refer to homogeneous mixtures, although the term solution in many occasions tends to be used more for mixtures in which the solvent is a liquid, the solute being able to be liquid, solid or gaseous.
The term solution, on the other hand, is used mostly when both the solvent and the solute are liquid. Likewise, both terms are used interchangeably in chemistry.
Components of a solution
Solutions have two different components:
Solvent the solvent is the substance in which the solute dissolves, it is generally the most predominant. It is also known as a solvent, dispersant, or dispersing medium.
Solute (s). In this case we are talking about the substance that is dissolved by the solvent. The same solution can have more than one solute dissolved in the same solvent. The solute is in less quantity than the solvent.
Properties of a solution
This is due to the fact that it is a homogeneous mixture, in which chemical reactions do not occur, but a different result is obtained in appearance and physical properties to its predecessor substances.
Their physical behavior is different from that of their separate components but, on the contrary, they leave the chemical properties of each one unaltered.
As in other mixtures, we can also obtain different types of solutions (and with them, different behaviors) through the final concentration of the solute in the solvent, thus being able to speak of:
Diluted solutions. Little solute in the same amount of solvent.
Concentrated solutions. Abundant solute in the same amount of solvent.
Saturated solutions. They achieve equilibrium between solute and solvent, without being able to add more solute, at least under certain given conditions of temperature and pressure.
Supersaturated solutions. They are solutions that contain more solute than the saturated solution would have at a certain temperature and pressure. If the temperature of a saturated solution is increased, it is possible to add more solute, but if it is allowed to cool slowly, it can transform into a supersaturated solution.
Examples of solutions are:
- Sugar dissolved in water.
- Salt dissolved in water.
- Sand dissolved in water.
- Alcohol dissolved in water.
- Vinegar dissolved in water.
- Carbon dioxide dissolved in water.
- Sulfur dioxide dissolved in water.
- Hydrogen dissolved in platinum.
- Gold dissolved in mercury.
- Carbon dissolved in iron (steel).
- Zinc dissolved in tin.
- Water vapor dissolved in the air.
- Sublimated iodine dissolved in nitrogen.