20 Examples of Pure Substances and Mixtures - encyclopedia

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Examples of pure substances
Mixtures
Solute and solvent
Examples of mixtures
Can serve you

All the matter that we know of the universe can be classified according to its constitution into two categories: pure substances and mixtures.

Thepure substances are those that are constituted, in principle, by a single chemical element or by the basic elements that make up its molecular structure, in case of being a compound.

A pure substance always retains the same physical and chemical properties, so it always responds in the same way to a given stimulus or reaction, such as the point of boiling wave density.

Pure substances, then, can be monatomic (like pure Helium), also called simple substances because they cannot be divided into their components; or compound substances (such as water: hydrogen + oxygen), since they include a fixed and stable proportion of basic elements that make it up.

Of course, a pure substance will always lack additional additives or any type of contaminant that alters its fundamental structure.

Examples of pure substances

Pure helium. Contained in gaseous state in the filling of party balloons, or among the components of the nuclear reactions of hydrogen, since it is a Noble gas, that is to say, a gas with very low reactivity and that therefore does not usually combine with other substances to form new chemical structures.
Pure water. Often referred to as water distilled, it is obtained through laboratory processes to avoid diluting any other environmental substance (since water is the largest known solvent). It is, thus, water made up solely of hydrogen and oxygen atoms (H₂O), nothing more.
Pure gold. Pure gold, 24 carats, is a unique elemental block, made up of gold (Au) atoms only and exclusively.
The diamonds. Although it may not seem like it, diamonds, one of the hardest known materials, are made up of atoms of carbon (C) only, arranged in such a particular way that their bonds are almost unbreakable.
Sulfur. This element of the periodic table is found in many simple or compound substances, since it is a very reactive element. Thus, we can name the acid sulfuric (H₂SW₄) as a pure substance, despite the fact that it contains hydrogen, sulfur and oxygen atoms, since they behave as one and only substance.
Ozone. A compound of rare appearance in our daily environment, but abundant in the pressures and temperatures of the high atmosphere, is ozone. It consists of a molecule similar to that of oxygen, but with three atoms of this element (O₃) and is often used precisely to purify water.
Benzene (C₆H₆). A hydrocarbon, that is, a union of carbon and hydrogen atoms, colorless, odorless, flammable and toxic, but obtainable in a state of purity, preserving its properties and reactions.
Sodium chloride (NaCl). Common salt, the one we have at home, is a pure compound substance. It is made up of two elements: chlorine and sodium. On the other hand, when we add it to the soup, it will be part of a rather complex mixture.
Carbon dioxide (CO₂). The gas that we expel after breathing and that plants require for their photosynthesis work. Composed of carbon and oxygen, it is usually dissolved (mixed) in the atmosphere along with other gases, but when it is taken by plants or manufactured in the laboratory, it is in its pure state.
Graphite. Another of the pure appearances of carbon, similar to diamond chemically, although not so physically. It is made up of carbon atoms only, in a much weaker and more malleable molecular alignment than diamonds.

Mixtures

The mixtures are the combination of two or more pure substances, in variable proportions and retaining many of their properties individual, thus obtaining a mixed substance whose components can be split by physical and / or chemical methods.

According to the mode of interaction of these components, the mixtures can be of two types:

Heterogeneous Mixtures. In them, the presence of the mixed elements can be observed, either with the naked eye or with laboratory equipment, since they are distributed in an irregular way, or in discernible phases. These mixtures can be, in turn, suspensions (observable physical particles in the solvent) or colloids (Physical particles are so tiny that they are not easily observable, and they are in constant motion and collision).
Homogeneous mixtures. The elements that make up these mixtures are very uniformly distributed and cannot be discerned with the naked eye. They are often called chemical solutions Or simply solutions, since its components (solute Y solvent) are not easily separable.

Solute and solvent

The solutions they are homogeneous mixtures, that is to say, indiscernible; but its components are called solute Y solvent according to the majority proportion of the second with respect to the first.

For example:

If in a liquid A few grams of the solid B, they may dissolve and we cannot see them with the naked eye, as we can still do with the liquid that contains them. However, if we evaporate this liquid, the grams of the solid will remain in the container that contained the solution. These types of processes are called methods of separation of matter.

Examples of mixtures

Gelatin. This colloidal mixture of collagens from animal cartilaginous matter is composed by mixing water and a solid in the presence of heat. Once a uniform (homogeneous) mixture is obtained, it is cooled to solidify and you get the usual children's dessert.
Kitchen fumes. Usually a mixture of propane and butane, the gases that we use to light the stove or oven are not discernible (homogeneous mixture) and share their ignition point, but they could perfectly be separated in the laboratory, taking advantage of some chemical or physical differences between the two.
Ambient air. We call air an indiscernible mixture of gases, among which are many monatomics (Oxygen, Hydrogen, etc.) and other compounds. Although at first glance they are not distinguishable, it is possible to separate them in the laboratory and obtain each one in its pure state.
Sea water. Seawater is far from pure: it contains you go out, compound substances product of chemical processes, chemical residues of life or human activities, in short, it is a more or less uniform mixture of its components. However, if we put seawater to dry in the sun, we will get the salt at the bottom of the container as the liquid evaporates.
The blood. Endless organic substances are dissolved in the blood, cells, enzymes, protein, nutrients and gases like oxygen. However, in a drop we cannot discern any of it, unless we see it under a microscope.
The Mayo. Mayonnaise is a cold emulsified sauce, mixture of egg and vegetable oil, neither of which is, in turn, a pure substance. So it is a very complex mixture of complex substances in which it is impossible to discern its components.
Sugar in a glass of water. In principle, sugar is soluble in water, so we can lose sight of its crystals as we pour them into the glass and stir with a teaspoon. However, if we continue adding (saturating the solution), we will achieve a concentration range such that the excess sugar remains at the bottom, that is, it does not form any more mixture.
Dirty water Water contaminated with soil or other waste substances allows the naked eye to see many of the solutes that cloud its transparency. These elements are in suspension in the liquid, so they can be removed by means of a filtering process.
The bronze. Like all alloys, bronze is the union of two different metals, such as copper and tin (pure substances). This allows the construction of metal parts that are not too stable, since their atoms do not build permanent bonds, and therefore malleable and ductile, but resistant. The invention of bronze was a true revolution for ancient humanity.
Rice with beans. As much as we stir them on the plate or in the pot, the beans and rice will be discernible with the naked eye, although we eat them together to enjoy their combined flavor. This is a very smorgasbord and perfectly siftable, if we wanted to separate them altogether.