Higher tungsten oxide

Tungsten oxide is considered to be one of the most refractory in this class of inorganic substances. In order to give a metal characteristic, we will analyze the qualities of the metal itself.

Features of tungsten

To understand the practical significance of tungsten oxide, we note that the metal itself has electrical resistance, a coefficient of linear expansion, a high melting point.

Pure tungsten has a high plasticity. The metal dissolves in acid only when heated to a temperature of 5000 ° C. It interacts with carbon, forming tungsten carbide as a reaction product. The obtained compound is characterized by increased strength.

The most common oxide of tungsten is tungsten anhydride. The main advantage of a chemical compound is the ability to reduce the powder to a metal, forming, as by-products, lower oxides.

The metal is distinguished by high density, brittleness and ability at low temperatures to form tungsten oxide.

Alloys of tungsten

Scientists distinguish single-phase types of alloys, which contain one or several elements. The most known is the connection of tungsten with molybdenum. Alloying of the alloy with a molybdenum element increases the tensile strength of tungsten.

Single-phase alloys are compounds: tungsten-zirconium, tungsten-hafnium, tungsten-niobium. The maximum plasticity of tungsten is given by rhenium. Its addition does not affect the parameters of the refractory metal.

Metal production

In the traditional way, it is impossible to obtain alloys of refractory tungsten: reaching the melting point, the metal instantly passes into a gaseous form. The main option for obtaining pure metal is electrolysis. Powder metallurgy is used in industrial quantities for the production of tungsten alloys. To do this, create special technological conditions using vacuum.

Being in nature

Tungsten oxide, the formula of which is WO ₃ , is called the higher compound. It is not found in nature in pure form, but is a part of tungsten ores. The process of mining and refining of refractory metal involves several stages.

The highest tungsten oxide is recovered from the ore mass. Further, the compound is enriched, and after treatment, pure metal is isolated.

In the process of manufacturing a thin tungsten wire, it is ensured that the impurities are completely removed. Otherwise, the technical characteristics of the finished product will be significantly reduced.

Spheres of use of tungsten

How to restore tungsten oxide? Hydrogen, interacting with this compound, helps to get pure metal. It is necessary in the manufacture of filaments, the creation of X-ray tubes, heaters and screens of vacuum furnaces, which are intended for use at high temperatures.

Steel, the alloying element in which is tungsten, has high strength properties. Products made from such an alloy are used in the manufacture of medical tools, cutting plates for drilling wells. The main advantage of the connection is the resistance to mechanical deformation.

The probability of occurrence of cracks and chips is quite low during operation. The most popular steel brand, which includes tungsten, is considered to be the winner.

From the scrap of this rare metal, high-quality catalysts, various paints, special pigments, etc. are manufactured. In the modern nuclear industry, tungsten and containers for radioactive waste are widely used.

Refractoriness of metal plays a special role in arc welding. Since tungsten in its pure form is considered to be a fairly rare metal, a procedure for the enrichment and processing of tungsten ore is carried out to obtain it. In its pure form, it has a light gray color with a characteristic metallic luster. Standard alloys of tungsten, called stellite, also include cobalt and chromium. The main component in such compounds is cobalt. Alloys are in demand in mechanical engineering.

Oxides of tungsten

What are the features of tungsten oxide (6), whose formula has the form WO ₃ ? The metal is capable of exhibiting different degrees of oxidation: the variants with the valency of the metal (4) and (6) have the maximum stability. The first compound of type WO ₂ refers to acid oxides and has the following characteristics: high melting point and special density. This chemical compound is almost insoluble in water, but in case of heating it can dissolve in acids and alkalis. In the chemical industry, it is used as a catalyst in some reactions. For example, WO _{2 is} used in the manufacture of ceramic products.

Tungsten oxide, having a valence (6), also exhibits characteristic acid properties. This compound reacts with alkalis, but is not able to dissolve in water. Given that the compound has a high melting point, it is used only as an accelerator of chemical processes.

Conclusion

In the course of inorganic chemistry, special attention is paid to the study of oxides, the analysis of their properties and the features of their application in industry. For example, at the final exam, nine-graders are offered a task with the following content: "Write down the formulas for the oxides of copper, iron, tungsten, and determine their basic chemical properties."

In order to successfully cope with the task, it is necessary to have an idea about the characteristics of oxides. These are considered binary compounds, in which the second element is oxygen. All oxides are classified into three groups: basic, acidic, amphoteric.

Iron and copper are elements of an auxiliary subgroup, so they are able to exhibit valence variables. For copper, it is possible to record only two variants of oxides, which exhibit the basic properties of Cu ₂ O and CuO.

Iron is not located in the main sub-group of chemical elements, therefore oxidation states of +2 and +3 take place. In these cases, oxides of the following species are formed: FeO and Fe2O3.

Tungsten in binary compounds with oxygen in most often exhibits valencies (4) and (6). Both oxides of this metal exhibit acidic properties, so they are used in the industry as accelerators of chemical processes.

The main purpose of all oxides of tungsten is the separation of pure metal, which is in demand in the chemical and metallurgical industries.