Many gaseous substances that exist in nature and are obtained during production are strong toxic compounds. It is known that chlorine was used as a biological weapon, bromine vapors have a very corrosive effect on the skin, hydrogen sulfide causes poisoning and so on.
One of these substances is carbon monoxide or carbon monoxide, the formula of which has its own characteristics in structure. It will be discussed further.
The chemical formula of carbon monoxide
The empirical form of the formula of the compound in question is as follows. However, this form gives a characteristic only of qualitative and quantitative composition, but does not affect the structural features and the order of the atoms in the molecule. And it differs from that in all other similar gases.
It is this feature that affects the physical and chemical properties exhibited by the compound. What is this structure?
Molecule structure
First, the empirical formula shows that the carbon valency in the compound is II. Just like oxygen. Therefore, each of them can form two bonds. The chemical formula of carbon monoxide CO clearly confirms this.
This is what happens. Between a carbon atom and oxygen by the mechanism of the socialization of unpaired electrons, the formation of a double covalent polar bond occurs. Thus, the structural formula of carbon monoxide takes the form C = O.
However, the molecular features do not end there. By the donor – acceptor mechanism, a third, dative, or semipolar bond is formed in the molecule. What is the reason for this? Since after the formation of covalent bonds in the exchange order, oxygen has two pairs of electrons, and the carbon atom has an empty orbital, the latter acts as an acceptor of one of the pairs of the first. In other words, a pair of oxygen electrons is placed on the free orbital of carbon and a bond is formed.
So, carbon is an acceptor, oxygen is a donor. Therefore, the formula of carbon monoxide in chemistry takes the following form: ≡. Such a structuring gives the molecule additional chemical stability and inertness in the manifested properties under ordinary conditions.
So, the bonds in the carbon monoxide molecule:
- two covalent polar formed by the exchange mechanism due to the socialization of unpaired electrons;
- one dative, formed by donor-acceptor interaction between a pair of electrons and a free orbital;
- total bonds in the molecule - three.
Physical properties
There are a number of characteristics that, like any other compound, carbon monoxide has. The formula of the substance makes it clear that the crystal lattice is molecular, the state under ordinary conditions is gaseous. The following physical parameters follow from this.
- ≡ - carbon monoxide (formula), density - 1.164 kg / m 3 .
- Boiling and melting points, respectively: 191/205 0 .
- It is soluble in: water (slightly), ether, benzene, alcohol, chloroform.
- It has no taste or smell.
- Colorless.
From a biological point of view, it is extremely dangerous for all living things, except for certain types of bacteria.
Chemical properties
From the point of view of chemical activity, one of the most inert substances under ordinary conditions is carbon monoxide. The formula, which reflects all the bonds in the molecule, confirms this. It is because of such a strong structure that this compound practically does not enter into any interactions at standard environmental parameters.
However, you should at least slightly heat the system, as the dative bond in the molecule breaks down, as do the covalent ones. Then carbon monoxide begins to exhibit active reducing properties, and quite strong. So, he is able to interact with:
- oxygen;
- chlorine
- alkalis (melts);
- with oxides and metal salts;
- with sulfur;
- slightly with water;
- with ammonia;
- with hydrogen.
Therefore, as already mentioned above, the properties that carbon monoxide exhibits, the formula largely explains it.
Being in nature
The main source of CO in the Earth’s atmosphere is forest fires. After all, the main way of the formation of this gas in a natural way is the incomplete combustion of various types of fuel, mainly of an organic nature.
Anthropogenic sources of air pollution with carbon monoxide are just as important and give in the mass fraction the same percentage as natural ones. These include:
- smoke from the work of factories and plants, metallurgical complexes and other industrial enterprises;
- exhaust gases from internal combustion engines.
Under natural conditions, carbon monoxide is easily oxidized by atmospheric oxygen and water vapor to carbon dioxide. This is the basis for first aid for poisoning with this compound.
Getting
It is worth pointing out one feature. Carbon monoxide (formula), carbon dioxide (molecular structure) respectively look like this: ≡ and = = . The difference is one oxygen atom. Therefore, the industrial method of producing monoxide is based on the reaction between dioxide and coal: 2 + = 2. This is the simplest and most common method for the synthesis of this compound.
In the laboratory, various organic compounds, metal salts and complex substances are used, since the yield of the product is not expected to be too large.
A high-quality reagent for the presence of carbon monoxide in air or a solution is palladium chloride. When they interact, a pure metal is formed, which causes darkening of the solution or surface of the paper.
Biological effect on the body
As already mentioned above, carbon monoxide is a very toxic, colorless, dangerous and deadly pest for the human body. Yes, and not just human, but in general any living thing. Plants that are under the influence of the exhaust gases of cars die very quickly.
What exactly is the biological effect of carbon monoxide on the internal environment of animal creatures? It is all about the formation of strong complex compounds of the hemoglobin blood protein and the gas in question. That is, instead of oxygen, poison molecules are captured. Cellular respiration is immediately blocked, gas exchange becomes impossible in its normal course.
The result is a gradual blockage of all hemoglobin molecules and, as a result, death. Only 80% of the damage is enough for the outcome of poisoning to become fatal. For this, the concentration of carbon monoxide in the air should be 0.1%.
The first signs by which you can determine the onset of poisoning with this compound are:
- headache;
- dizziness;
- loss of consciousness.
First aid - go out into the fresh air, where carbon monoxide under the influence of oxygen will turn into carbon dioxide, that is, it will be neutralized. Cases of deaths from the action of the substance in question are very frequent, especially in houses with stove heating. Indeed, during the combustion of firewood, coal and another type of fuel, this gas is necessarily formed as a by-product. Compliance with safety regulations is essential to preserving human life and health.
There are also many cases of poisoning in garage rooms, where many working car engines are collected, but the influx of fresh air is not enough. Death in excess of the permissible concentration occurs within an hour. It is physically impossible to sense the presence of gas, because it has no smell or color.
Industrial use
In the metallurgical industry, carbon monoxide is often used for the reactions of the reduction of metals from their oxides or salts. The formula for the resulting compound is CO 2 . A pure substance , metal, is also formed.
In addition, carbon monoxide is used:
- for processing meat and fish products, which allows you to give them a fresh look;
- for the synthesis of certain organic compounds;
- as a component of generator gas.
Therefore, this substance is not only harmful and dangerous, but also very useful for humans and their economic activities.