Alkali metal compounds and their use

Of the entire periodic system, most of the elements are a group of metals. Alkaline, alkaline earth, amphoteric, transient, radioactive - there are a lot of them. All metals play a huge role not only in nature and human biological life, but also in various industries. No wonder the 20th century was called "iron".

Metals: a general characteristic

All metals are united by common chemical and physical properties, by which they are easily distinguished from non-metallic substances. So, for example, the structure of the crystal lattice allows them to be:

• Conductors of electric current;
• Good heat conductors;
• Forging and plastic;
• Durable and shiny.

Of course, there are differences among them. Some metals shine with silvery color, others - more matte white, others - generally red and yellow. There are also differences in the parameters of heat and electrical conductivity. However, all the same these parameters are common for all metals, while nonmetals have more differences than similarities.

In chemical nature, all metals are reducing agents. Depending on the reaction conditions and specific substances may act as oxidants, but rarely. Are able to form numerous substances. Chemical compounds of metals occur in nature in a huge amount in the composition of ore or minerals, minerals and other rocks. The degree of oxidation of metals is always positive, it can be constant (aluminum, sodium, calcium) or variable (chromium, iron, copper, manganese).

Many of them are widely used as building materials, used in a wide range of branches of science and technology.

Chemical compounds of metals

Among these are several main classes of substances that are products of the interaction of metals with other elements and substances.

1. Oxides, hydrides, nitrides, silicides, phosphides, ozonides, carbides, sulphides and others - binary compounds with nonmetals, most often belong to the class of salts (except oxides).
2. Hydroxides are the general formula Me ^{+ x} (OH) _x .
3. Salt. Compounds of metals with acid residues. Can be different:

• Average;
• Acid;
• Double;
• Basic;
• Complex.

4. Compounds of metals with organic substances - organometallic structures.

5. Compounds of metals with each other - alloys, which are obtained in different ways.

Metal connection options

Substances in which two different metals and more can simultaneously be located are divided into:

• Alloys;
• Double salts;
• Complex compounds;
• Intermetallides.

Methods of connecting metals with each other also vary. For example, to obtain alloys, the method of melting, mixing and solidifying the obtained product is used.

Intermetallides are formed as a result of direct chemical reactions between metals, often occurring with an explosion (for example, zinc and nickel). For such processes, special conditions are required: the temperature is very high, pressure, vacuum, absence of oxygen, and others.

Double salts and complex compounds can form when the solutions of the starting materials are drained, as well as when they are melted.

The manufacture of metal products also implies their interconnection. To do this, use methods such as:

• Welding (gas, electric and so on);
• Soldering with different kinds of solders;
• thread;
• Riveting.

The main condition is to create such a product that can be resistant to corrosion and in which there will be no seams and impurities, cracks.

Alkali metal compounds and their use

Alkaline are the elements located in the first group of the main subgroup of the periodic table. They are only 6, and they were open almost all at the same time with a small time interval. In the form of simple substances in nature, these elements do not occur.

Due to the high chemical activity, it is very difficult and dangerous to work with them. Therefore, I had to work hard to distinguish them in pure form. Much earlier, people began to use various compounds of alkali metals. Some of them have been known since antiquity and have not lost importance and relevance today. They are used in engineering, construction, medicine, food industry, chemical industry, metallurgy, machine building, agriculture and many other sections of the national economy. The main ones are discussed in more detail.

Types of connection of alkali metals with other metals belong to the following groups:

• Intermetallic compounds;
• Complex compounds;
• Double salts.

Oxides

Of all the alkali metals during combustion in oxygen, the normal oxide is capable of producing only lithium. The rest show excessive activity, therefore, peroxide Me ₂ O _{2 is formed} . From peroxides, a simple metal can produce an oxide of the normal form Me ₂ O. Oxygen compounds of alkali metals have a different color.

1. Lithium, potassium and sodium oxide are white crystalline powders.
2. Rubidium is the yellow color of the oxide.
3. Cesium is orange.

The main field of application is the chemical industry. Alkali metal oxides react with water, forming important compounds - alkalis. This property is the reason for the name of this group of elements. Alkali metal compounds - oxides - are only a fraction of the total mass of significant and important substances that make up these elements.

Hydroxides (alkalis)

The compounds of alkali metals with hydroxo group are called alkalis, or hydroxides. All of them are very corrosive substances, capable of easily destroying almost any material. Especially it concerns animal tissues. Therefore, work with alkalis should be extremely cautious, in the place of contact with the skin can cause a deep chemical burn.

The most famous substance among alkalis is caustic soda, or sodium hydroxide. This compound is known since ancient times, where it was extracted from the ash of plants and used for soap making and laundry. The chemical formula is NaOH. Today, caustic soda is produced in huge quantities in every country, since virtually no industry is involved without its participation. It is used:

• In the oil refining industry;
• In cosmetic and perfumery;
• In chemical synthesis;
• For the production of cleaning and cleaning agents, abrasive materials;
• In the leather and textile industries and other areas.

Other metals from the alkali group form less important and widespread alkalis. More or less significant is potassium hydroxide - KOH, which is known as caustic potassium.

Salt

Such alkali metal compounds as salts are not only practically in demand substances, but also present in the body of living beings, maintaining their normal viability.

The most important salt is, of course, sodium chloride. This is the common table salt that every home has and is not given much importance due to its high prevalence. However, if you imagine that it suddenly disappears, few people will rejoice at the consequences. Unsalted food is difficult, in addition, it causes irreparable harm to health, since the body does not receive sodium ions needed for the work of the heart and blood vessels.

Also, important alkali metal compounds are carbonates. Especially carbonate and sodium bicarbonate, which in common people is called soda. It is used in the production of glass, for the manufacture of detergents. Soda can safely clean the dishes. It has good disinfecting, disinfecting, cleansing and bleaching properties. Widely used in the food industry, especially in confectionery and bakery. With its help soap is cooked, create washing powders.

Soda, salt, caustic are all compounds of alkali metals in nature. They exist in pure form, forming deposits, or are part of the combustion products of certain substances. Sometimes they are obtained in a laboratory way. But always these substances are important and valuable, as they surround the person and shape his life.

The alkali metal compounds and their use are not limited to sodium. Also popular and popular in the economy are such salts as:

• Potassium chloride;
• Potassium nitrate (potassium nitrate);
• Potassium carbonate;
• sulfate.

All of them are valuable mineral fertilizers used in agriculture.

Alkaline earth metals - compounds and their application

This category includes elements of the second group of the main subgroup of the system of chemical elements. Their constant degree of oxidation is +2. These are active reducing agents that readily enter into chemical reactions with most compounds and simple substances. They show all the typical properties of metals: gloss, ductility, heat and electrical conductivity.

The most important and common of them are magnesium and calcium. Beryllium shows amphotericity, barium and radium refer to rare elements. All of them are capable of forming the following types of connections:

• Intermetallic;
• Oxides;
• Hydrides;
• Binary salts (compounds with nonmetals);
• Hydroxides;
• Salts (double, complex, acidic, basic, medium).

Consider the most important compounds from a practical point of view and their field of application.

Salts of magnesium and calcium

Such alkaline earth metal compounds, as salts, are important for living organisms. After all, calcium salts are the source of this element in the body. And without it, the normal formation of the skeleton, teeth, horns in animals, hooves, hair and wool cover and so on is impossible.

Thus, the most common salt of the alkaline earth metal of calcium is carbonate. Its other names are:

• a piece of chalk;
• marble;
• limestone;
• dolomite.

It is used not only as a supplier of calcium ions in a living organism, but also as a building material, raw material for chemical industries, in the cosmetic industry, glass industry and so on.

Such alkaline earth metal compounds, such as sulfates, are also important. For example, barium sulfate (the medical name "barite porridge") is used in X-ray diagnostics. Calcium sulphate in the form of crystalline hydrate is a gypsum that is contained in nature. It is used in medicine, building, stamping casts.

Phosphors from alkaline earth metals

These substances are known since the Middle Ages. Earlier they were called phosphors. This name is found now. By their nature these compounds are magnesium, strontium, barium, calcium sulfides.

With a certain treatment, they are able to show phosphorescent properties, and the glow is very beautiful, from red to bright violet. This is used in the manufacture of road signs, overalls and other things.

Complex compounds

Substances that include two or more different elements of a metallic nature are complex metal compounds. Most often they are liquids that have beautiful and colorful colors. Used in analytical chemistry for the qualitative determination of ions.

Such substances are able to form not only alkaline and alkaline earth metals, but all the others. There are hydrocomplexes, aquacomplexes and others.