GOLD IN CHEMICS

Gold is a metal with unusual, contradictory properties for this group of materials: inelastic and soft, but of great value. Its characteristics improve when it forms compounds and interacts with other substances. And the metal can change from one state to another when environmental parameters change.

Such a variety of characteristics allows its use for various purposes: the properties of the precious metal are studied in educational institutions, the material is used in research, it is used as an active component in the performance of various industrial technologies and for the production of products.

Gold in Chemistry: reports, reports, presentations, essays

The properties of the precious metal have been known for a long time. Because of them, as well as its structure, the metal is widely used for the development of various industries. Its characteristics begin to be studied in chemistry classes at school, where they first learn about the metal's ability to react with different substances and environments. For example, gold is susceptible to fluorine under certain conditions, but it does not change its properties when it comes into contact with oxygen.

This feature allowed it to be used to protect other metals from oxidation (perform gold plating).

Another feature that allows the use of gold is its electrical conductivity. The metal is known for its reflectivity, which makes it possible to cover various structures and objects (mirrors, spacecraft). In addition, gold can absorb short wavelengths. This makes the material yellow. This is explained by the fact that initially all metals are gray, their color is close to silver-white. However, gold not only absorbs short wavelengths (close to the violet hue), but also reflects the longer wavelengths of the light spectrum.

As a result of this process, the metal acquires the familiar yellow color.

Gold in primary deposits rarely exists in pure form

Gold in the Mendeleev Table - Au (Aurum)

Gold is an element of the Mendeleev table. It occupies a special place in the system of chemical substances: it belongs to the 11th group, the sixth period, and is contained under the number 79. It is called in Latin Au, and is read, spelled and pronounced the same way: aurum. It is a noble metal, but in its pure form it has no economic value.

It gets its name from its distinctive yellow color (aurum comes from the ancient ausum, meaning "yellow").

When one studies the Mendeleev system, one learns that gold is not adjacent to other precious metals. However, the symbol Atsassociates with platinum and silver. These materials are often used in the production of the same items. The atomic mass of aurum is 196, 966569 grams/mol.

Gold is found in the earth's crust, in water. It is a scattered precious metal, found in minerals. Compounds with it occur infrequently, mostly crennerite and kaleverite. Nuggets can be found, but rarely, and they are all named.

Most often for the production of precious metal ore is used, which contains individual inclusions - particles.

Chemical and physical properties of the metal

The widespread designation of gold (sign Au) is part of the name of different compounds, for example, with fluorine. And it is this variant that is defined as the most stable. Under other conditions, the precious metal quickly loses its properties. This is due to its chemical characteristics:

is characterized by inertia;
It shows resistance to alkalis and acids, which distinguishes the precious metal from other materials;
dissolves under the influence of different environments (more often an aggressive nature);
does not interact with oxygen, water;
is restored to solid material;
forms compounds that are not stable, their use makes it possible to obtain explosive mixtures.

The physical properties are also widely known:

ability to conduct heat;
a small electrical resistance index;
high density;
Low Mohs hardness score (makes the precious metal soft);
increased ductility, which necessitated the use of ligatures to produce a harder alloy.

Melting gold at home is best done with small crucibles

Analytical chemistry in a test tube

Thanks to the knowledge that reactions with gold produce completely different materials, it was possible to create this precious metal artificially. However, in the same form as the natural inclusions that ore usually contains, it is produced in an extremely complex way. This requires a nuclear reactor, where many elements are converted into other elements.

This method has been used before, when some amount of precious metal was produced artificially. It took only 100 mg of mercury.

But the process of forming the valuable metal is quite expensive. In addition, most compounds are not stable. As a result, the cost of such material will increase many times. Other types of artificial gold are also considered:

tin sulfide (gold leaf, is a particle - soft flakes), darkens at high temperature, decomposes;
Titanium gilding: is not a true precious metal, but only looks appropriate (there is no hallmark on such products).

Gold precipitation Dissolving gold Refining of gold with aqua regia

Interesting facts about gold in chemistry

Not everyone knows that the chemical formula of the noble metal has been used for a long time, even for the development of the sciences that preceded chemistry. The properties of this material came in handy one day to produce glass with unusual properties. Several centuries ago, M. V. Lomonosov revived the art of the smalt mosaic and initiated the production of glass beads. That was also when the "golden ruby" glass appeared. The main characteristic was the rich red color given by the gold compounds.