Inorganic acids are very important in the chemical industry. After all, they are raw materials for many syntheses, catalyze processes, act as water-removing agents during dehydration, and so on.
However, even more valuable are their s alts - the products of substitution of hydrogen for a metal in the composition of their molecules. Carbonic acid is special in this respect. After all, by itself, it practically does not exist, in the air it immediately decomposes into carbon dioxide and water. But carbonic acid forms s alts that have been known to man since ancient times. They are very popular in many areas of production and activity. We will consider them.
S alts of carbonic acid: classification
First of all, it should immediately be pointed out that the substances in question can be called differently. It just so happened that all the names have taken root and are used to this day, both historically established or trivial, and data on rational nomenclature. So, s alts of carbonic acid, they are called like this:
- carbonates;
- bicarbonates;
- carbon dioxide;
- bicarbonate;
- hydrocarbons.
Soof course, each has its own common name, which is individual.
The above names immediately reflect the classification of the compounds under consideration. Since the acid is dibasic, it also forms s alts of two types:
- medium;
- sour.
The prefixes hydro- or bi- are added to the name of the latter. Almost every s alt of an alkali or alkaline earth metal is practically an important compound that people need in their economic activities.
History of discovery and use
Since ancient times people have known s alts of carbonic acid. Indeed, even in ancient Egypt, construction was carried out using gypsum, alabaster, limestone and marble.
In the writings of Pliny the Elder, the technological process of obtaining lime by burning limestone is mentioned. The famous wonder of the world - the pyramids - were erected using gypsum and materials obtained from it. Potash was obtained from the ashes of plants and used to wash clothes, and then in soap making.
That is, people almost always knew how to use the products that nature gives. However, the fact that these are carbonic acid s alts, what structure they have, how they can be synthesized artificially, and what their other characteristics are, became known much later, already in the 17th-18th centuries.
Today, many carbonates of alkali and alkaline earth metals are also widely used, some of them acceptan important part in groundwater circulation processes.
Deposits in nature
By percentage, the considered minerals occupy approximately 5% of the entire mass of the earth's crust. They are formed mainly outside, forming rocks. Also, many s alts are formed by hydrothermal processes.
Microorganisms, mollusks and other animals and plants contribute to the formation of carbonates by biochemical means. Often s alts of carbonic acid are found in ores, accompanying them by forming associates.
The most famous minerals and rocks of these compounds:
- calcite;
- dolomite;
- chalk;
- marble;
- limestone;
- gypsum;
- magnesite;
- siderite;
- malachite.
Methods of obtaining and application
S alts of carbonic acid are called carbonates (if we are talking about medium variations). This means that they necessarily include a carbonate ion, the formula of which is CO32-. To complete the full view, it is the s alt that lacks only the metal cation and indices reflecting the quantitative composition of the compound. This is used in laboratory methods for obtaining these substances.
After all, in addition to extraction from natural sources, carbonic s alts can also be synthesized by the reactions of exchange, combination and substitution. However, such methods have no practical significance, since the product yield is too small and energy-consuming.
Where is the use of s alts of carbonic acid, in what areas? Foreach of them is individual, but in general, several main industries can be identified.
- Construction business.
- Chemical industry.
- Glass production.
- Soap making.
- Paper synthesis.
- Food industry.
- Production of detergents and cleaning products.
- Calcium carbonates are a source of metal ions in the body of living beings.
Let's look specifically at a few examples of carbonates, their composition and significance.
Calcium carbonate
As mentioned above, this substance is a source of calcium ions Ca2+ in the human body. And this is very important. After all, they take part in maintaining the constancy of the blood buffer system, are part of the bones, nails, hair, strengthen tooth enamel.
With a lack of calcium, various diseases develop, including such dangerous ones as heart failure, osteoporosis, pathological changes in the lens of the eyeball and others.
In addition, calcium carbonate is also used in the construction industry. After all, its varieties are:
- chalk;
- marble;
- limestone.
Deposits of this s alt are rich enough that a person does not experience a deficit in it. Often it is sold in purified form in the form of tablets, as in the photo below. True, in order for calcium to be absorbed well enough, the presence of vitamin D is required.
Sodium carbonate
Coal s altacids - carbonates - are also important in human households. So, sodium carbonate, or sodium carbonate, in the common people is called soda. However, this is not a substance that is an important part in the preparation of various dishes. No, this s alt is used for household purposes for cleaning household surfaces of products: bathtubs, sinks, dishes and others. It is better known as soda ash or laundry soda, it is also used in glass production, soap making.
The formula of this compound is Na2CO310H2O. This is an average aqueous s alt related to crystalline hydrates. It occurs in nature in the form of minerals and in the composition of rocks. Examples:
- throne;
- nakholit;
- thermonatrite.
Often isolated from seaweed, their ash. It was this method that was used in antiquity to obtain raw materials for the production of soap or simply to wash clothes. The richest plant containing this s alt is soda-bearing hodgepodge. Its ash is the most acceptable for obtaining sodium carbonate.
Potash
The formula for the s alt of carbonic acid, which has this name, is K2CO3. It is a white crystalline hygroscopic powder. Medium anhydrous s alt which has very good solubility. This compound has also been known to people for a long time, and it is widely used today. Name synonyms:
- potassium carbonate;
- potash;
- potassium carbonate.
The main uses are as follows.
- Asreagent in liquid soap production processes.
- For the synthesis of crystal and optical glass, refractory glass.
- For dyeing fabrics.
- As fertilizer for crops.
- In the construction industry - to reduce the freezing point of building mixtures.
- In the photo case.
The main industrial method for obtaining this s alt is the electrolysis of calcium chloride. This forms hydroxide, which reacts with carbon dioxide and forms potash. Natural raw materials are the ashes of cereals and algae, which contain a lot of it.
Drinking soda
Acid s alts of carbonic acid are no less important than the average. So, for example, sodium bicarbonate, whose formula is NaHCO3. Its other name, better known to everyone, is drinking soda. Outwardly, it is a white fine powder, which is very soluble in water. The compound is unstable when heated, it immediately decomposes into carbon dioxide, water and an average s alt. This allows the use of baking soda as a buffer in the internal environment of living organisms.
There are also several more applications for this compound:
- food (especially confectionery) industry;
- medicine (for treating burns with acids);
- in chemical syntheses in the production of plastics, dyes, foam plastics, household chemicals;
- in the light and textile industry (tanning of leather, finishing of silk fabrics, etc.);
- used whenproduction of carbonated drinks and various culinary dishes;
- Fire extinguishers are filled with sodium bicarbonate.
Calcium bicarbonate
This acidic carbonic acid is an important part in groundwater circulation. This compound provides the formation of temporary water hardness, which is eliminated by boiling. At the same time, it is calcium bicarbonate that contributes to the mass movements of carbonates in nature, that is, it carries out their circulation. The formula for this compound is Ca(HCO3)2.
