Chemistry studies substances and their properties. When they are mixed, mixtures are created that acquire new valuable qualities.
What is a mixture
A mixture is a collection of individual substances. They are not only made by scientists in laboratories under certain conditions. Every day we start with fragrant tea or coffee, to which we add sugar. Or we cook a delicious soup, which must be s alted. These are the real mixtures. Only we don't think about it at all.
If it is impossible to distinguish particles of substances with the naked eye, then you have homogeneous mixtures (homogeneous). They can be obtained by dissolving the same sugar in tea or coffee.
But if you add sand to sugar, their particles can be easily distinguished. Such a mixture is considered heterogeneous or heterogeneous.
Heterogeneous mixtures
In the manufacture of mixtures of this type, you can use substances that are in a different state of aggregation: solid or liquid. A mixture of ground peppers of different types or other seasonings are most often heterogeneous dry compositions.
If any liquid is used in the process of preparing a heterogeneous product, then the resultingmass is called suspension. And there are several types of them. When liquids are mixed with solids, suspensions are formed. Their example is a mixture of water with sand or clay. When a builder makes cement, a cook mixes flour with water, a child brushes his teeth with toothpaste, they all use slurries.
Another variety of heterogeneous mixtures can be obtained by mixing two liquids. Naturally, if their particles are distinguishable. Drip vegetable oil into water and get an emulsion.
Homogeneous mixtures
The most famous of this group of substances is air. Every student knows that it contains a number of gases: nitrogen, oxygen, carbon dioxide, water vapor and impurities. Can they be seen and seen with the naked eye? Of course not.
Thus, both air and sweet water are homogeneous mixtures. They can be in different aggregate states. But most often liquid homogeneous mixtures are used. They consist of a solvent and a solute. Moreover, the first component is either liquid or taken in a larger volume.
Substances cannot dissolve in an infinite amount. For example, only two kilograms of sugar can be added to a liter of water. Further, this process simply will not occur. Such a solution will become saturated.
Solid homogeneous mixtures are an interesting phenomenon. So, hydrogen is easily distributed in various metals. The intensity of the dissolution process depends on manyfactors. It increases with an increase in the temperature of the liquid and air, during grinding of substances and as a result of their mixing.
Surprising is the fact that absolutely insoluble substances do not exist in nature. Even silver ions are distributed between water molecules, forming a homogeneous mixture. Such solutions are widely used in everyday life and human life. For example, everyone's favorite and he althy milk is a homogeneous mixture.
Methods for separating mixtures
Sometimes it becomes necessary not only to obtain homogeneous solutions, but also to separate homogeneous mixtures. Let's say there is only s alt water in the house, but you need to get its crystals separately. To do this, a similar mass is evaporated. Homogeneous mixtures, examples of which were given above, are most often separated in this way.
Distillation is based on differences in boiling point. Everyone knows that water begins to evaporate at 100 degrees Celsius, and ethyl alcohol at 78. A mixture of these liquids is heated. First, the alcohol vapor evaporates. They are condensed, that is, they are transferred to a liquid state, in contact with any chilled surface.
Metal mixtures are separated using a magnet. For example, iron and wood chips. Vegetable oil and water can be obtained separately by settling.
Heterogeneous and homogeneous mixtures, examples of which are illustrated in the article, are of great economic importance. Minerals, air, groundwater, seas, food,building materials, drinks, pastes - all this is a combination of individual substances, without which life would be simply impossible.
