The blends are combinations of two substances that, when in contact, do not proceed to form a chemical reaction.
At the time when two substances form a mixture, depending on the properties of each substance, the conditions under which the mixture is formed, among other factors, homogeneous mixtures may be formed (mixtures whose components cannot be distinguished with the naked eye) or heterogeneous (mixtures whose components can be distinguished with the naked eye or by means of a measuring instrument). It is difficult to classify mixtures, as there are many types with relatively similar characteristics, but broadly speaking they are usually differentiated into:
- solutions. They are homogeneous mixtures. They are uniform, that is, any volume taken from a solution will have the same composition of its components. They are composed of a majority substance, called solvent, and one that is in lesser quantity, called solute. When the volumes of the different components of a solution are added, the final volume is not equal to this sum, since there are interactions between these components.
- colloids. They are mixtures with intermediate properties between homogeneous and heterogeneous. They are made up of two phases, a dispersed one that is in a smaller proportion and a continuous one that is in a greater proportion.
- Suspensions. They are heterogeneous mixtures. They are generally formed by solid particles suspended in some liquid.
Mixtures can be formed between substances that are in any state of aggregation, and the state of aggregation of the mixture is almost always the same as that of the substance that is in the greater amount.
Gas-liquid mixtures
Regarding the combinations of a substance in a liquid state and another in a gaseous state, the mixtures can appear having the gas in greater or lesser quantity:
- Gas mixture (liquid in gas). The gas can appear as a solvent when the liquid acts as a solute, that is, when the gas appears in greater proportion. This happens on rare occasions, for example in the water vapor in the air, which is considered a solution where the liquid particles dissolve in the gas. Although there are environments that are especially endowed with this vapor, the humidity in the air is something that is always present to a greater or lesser extent, so the combination can be seen at any time and place. On the other hand, some aerosols are colloidal mixtures of liquids in gases.
- Liquid mixture (gas in liquid). On other occasions, the gas is the substance that occupies a smaller proportion of the mixture, leaving the largest place for the liquid. This is the case of the dissolution of carbon dioxide in water, used to prepare drinks. There are also colloid-type mixtures of a gas in a liquid, such as shaving cream.
Examples of mixtures of liquids and gases
The following list brings together some examples of mixtures in which there is a liquid and a gaseous component.
- fizzy drinks.
- Dew, liquid particles in a gaseous medium.
- A bottle of beer.
- The foam of a shampoo.
- A cloud.
- A whipped egg white (liquid with air incorporated in its structure)
- Sparkling drinks.
- The oxygen of the sea.
- The water vapor present in the air.
Other specific blends
- gas mixtures
- Gas mixtures with solids
- Mixtures of solids with liquids