There are three classes of complex inorganic compounds: oxides, hydroxides (which include acids and bases), and s alts. Many metals and non-metals can form oxides, hydroxides, and also be part of acidic residues. So, phosphorus is included in the acid residue PO4. There are several varieties of phosphorus oxide. Accordingly, there are various hydroxides of it, which are formed from these oxides. The highest phosphorus hydroxide is phosphoric acid. In this article, we will consider the physical and chemical properties of this element and its compounds, as well as talk about its prevalence in nature and other interesting facts.
Physical properties of phosphorus
It can exist in various variations. Phosphorus is a substance that consists of one chemical element. Its atoms do not combine into molecules. The formula of phosphorus is R. However, depending on the structure of the crystal lattice, this element can exist in the form of three substances.
The most common is white phosphorus - it has a waxy structure and high toxicity. The melting point of this substance is forty-four degrees Celsius, and the boiling point is two hundred and eighty degrees. With friction givenmaterial, it ignites very quickly, so they cut it only by placing it in an aquatic environment. If you heat it for a long time at a temperature of two hundred and fifty degrees Celsius, it turns into red phosphorus. This substance is presented in the form of a brown-red powder. Red phosphorus, unlike white, is not poisonous.
The most stable form of existence of this element can be called black phosphorus, which by some external features is similar to metal: it has a peculiar luster, has high hardness, electrical and thermal conductivity.
From the point of view of chemistry
Phosphorus is a chemical element that is in the fifth group and third period in the periodic table. From this we can conclude that its valency is five. In addition, from the periodic table it can be seen that the element phosphorus has an atomic mass of thirty-one grams per mole. This means that 1 mole of a substance will weigh 31 one grams. Considering the chemical properties of phosphorus, we will talk about its reactions with simple as well as complex compounds.
Interaction with simple substances
The first thing you need to pay attention to is the oxidation of phosphorus. This is his reaction with oxygen. As a result, two different substances can be formed - everything will depend on the proportions of these components.
The first option - four moles of phosphorus and three moles of oxygen form two moles of phosphorus trioxide. Such a chemical interaction can be written using the followingequation: 4P + 3O2=2P2O3.
The second option is the formation of four moles of phosphorus and five moles of oxygen, two moles of phosphorus pentoxide. This reaction can be expressed using the following equation:
In both chemical reactions, there is a significant release of light. In addition, phosphorus can interact with such simple substances as metals, halogens (fluorine, iodine, bromine, chlorine), sulfur. This chemical element is capable of exhibiting both reducing and oxidizing properties. An example of interaction with halogens is chlorination. It takes place in two stages. The first is the formation of two moles of phosphorus trichlorate from two moles of the non-metal in question and three moles of chlorine. This interaction can be expressed using the following equation: 2P +3Cl2=2PCl3.
The second stage of this process is the addition of chlorine atoms to the already obtained phosphorus trichlorate. Thus, when the same volume of chlorine is added to one mole of the latter, one mole of phosphorus pentachlorate is formed. We write the equation for this reaction as follows: PCl3 + Cl2=PCl5.
The regularities of the interaction of phosphorus with metals can be seen in this example. If we take three moles of potassium and one mole of phosphorus, we get one mole of potassium phosphide. This kind of process can be written using the following reaction equation: 3K + P=K3P.
Interaction withcomplex substances
Complex chemical compounds with which phosphorus can react include acids and s alts. Let us describe in order the features of the contact of the element under consideration with these groups of chemicals.
Phosphorus and acids
Among all others, the interaction of phosphorus and nitric acid stands out. To carry out this kind of reaction, it is necessary to take the following components: phosphorus in the amount of three moles, five moles of nitrate acid, and also water - two moles. As a result of such chemical interaction, we obtain the following products: phosphoric acid and nitrogen oxide. The equation for this reaction is written as follows: 4 + 5NO.
Phosphorus and s alts
This kind of chemical interaction can be considered on the example of the reaction of the considered non-metal with cuprum sulfate. To carry out this process, it is necessary to take two moles of phosphorus, five moles of copper sulfate, eight moles of water. As a result of the interaction of these substances, we obtain the following chemical compounds: sulfate acid in the amount of five moles, pure copper - the same amount, and phosphoric acid - two moles. This process can be written in the form of the following equation: SO4 + 5Cu + 2H3PO4.
Getting this non-metal
In industry, the substance in question is extracted from a chemical compound such as calcium phosphate. For thisthe following chemical reaction is carried out: the indicated s alt is mixed with sand (silicon oxide) and carbon in molar proportions of 1:3:5, as a result, calcium silicate, phosphorus and chad gas are obtained in a molar ratio of 3:2:5.
Phosphorus compounds and their properties
The most common of the compounds of the considered non-metal is phosphorus hydroxide. It can be of several types depending on the oxide from which it is formed. Phosphorus hydroxide can be obtained by carrying out a chemical reaction between its oxide and water. Due to these reactions, various types of substances are formed. Thus, hydroxide (3) can be obtained from trioxide, and phosphorus hydroxide (5) from pentoxide. These substances have acidic properties and are capable, in turn, of reacting with metals, s alts, bases, etc.
The highest phosphorus hydroxide is phosphoric acid. It is oxygenated and tribasic. Its formula is H3PO4.
Basic chemical properties
Phosphorus hydroxide, the formula of which is given above, is able to react with both simple and complex substances. Let's take a closer look at these processes.
Reactions of phosphoric acid with metals
Like other chemical compounds of this class, phosphorus hydroxide is able to interact with metals. During this process, a displacement reaction occurs in which metal atoms displace hydrogen atoms, thereby forming s alt and hydrogen, which is released into the air as a gas with an unpleasant odor. In order for this reactioncould be realized, the metal must be located to the left of hydrogen in the electrochemical series of activity. That is, substances such as copper, silver and others like them are not able to react with phosphoric acid, since due to their low chemical activity they will not be able to displace hydrogen atoms from their compounds.
Take aluminum as an example. When two moles of this element are added to two moles of phosphorus hydroxide, we get aluminum phosphate and hydrogen in an amount of 2 and 3 moles, respectively. The equation for this reaction is written as follows: 2Al + 2H3PO4=2AlPO4 + 3H 2.
Interaction with bases
Phosphorus hydroxide, like many other acids, can enter into chemical reactions with bases. Such processes are called exchange reactions. As a result, a new hydroxide is formed, as well as a new acid. Such reactions can only take place if one of the resulting products is insoluble in water, that is, it precipitates, evaporates as a gas, or is water or a very weak electrolyte.
Phosphoric acid and s alts
In this case, an exchange reaction also occurs. As a result, you can get a new acid and s alt. In order for this kind of reaction to take place, the rule that was described just above must also be observed.
Use of phosphorus and its compounds in industry
First of all, the compounds of this chemical element are used formaking a mixture that is applied to the side surface of matchboxes. The match heads themselves are also treated with a mixture containing phosphorus.
The pentoxide of the considered non-metal is widely used as a gas dryer. It is also used in the chemical industry in order to obtain phosphorus hydroxide, the formula and properties of which were discussed above. In addition, it is used in the manufacture of glass.
Phosphorus hydroxide is also used in many industries. First of all, it is used in the manufacture of fertilizers. This is due to the fact that phosphorus is simply vital for plants. Therefore, there are a number of different fertilizers that are made on the basis of the compound of the non-metal in question. For these purposes, substances such as calcium phosphate are used. S alt is used as a fertilizer in ground form. In addition, ordinary and double superphosphate are used for this. Ammophos and nitroammophos can also serve as a fertilizer. In addition to all of the above, s alts or phosphorus hydroxide are used as a reagent to determine the presence of silver compounds in a solution. So, a substance is added, which includes the acid residue PO4, to the solution. If the latter contains s alts or silver hydroxide, a rich yellow precipitate will form. This is argentum phosphate, which has the following chemical formula: AgNO3.
Structure of the phosphorus atom
As you know, all atoms consist of a nucleus and electrons rotatingAround him. The nucleus contains protons and neutrons. Electrons have a negative charge, protons have a positive charge, and neutrons have a zero charge. The serial number of phosphorus in the periodic table is fifteen. From this we can conclude that its nucleus contains fifteen protons. If the atom is neutral and not an ion, then there are as many electrons as there are protons. That is, in the case of phosphorus, there are fifteen of them.
If one of the electrons leaves its orbit, the atom will turn into a positively charged ion, that is, a cation. If one electron joins, a negatively charged ion is formed - an anion.
In the periodic table of chemical elements, you can see that phosphorus belongs to the third period. From this it is clear that there are three orbits around the nucleus, on which electrons are evenly distributed. The first has two, the second has eight, and the third has five.
Prevalence in nature
The mass fraction of phosphorus in the earth's crust is 0.08%. It is not a very common chemical element in nature. However, there is a whole group of minerals that include phosphorus. These are apatites, as well as phosphorites. The most common of the first group is fluorapatite. Its chemical formula is as follows: 3Ca3(PO4)2•CaF2. It comes in transparent, green and turquoise shades. Among phosphorites, calcium phosphate is the most common, having the following chemical formula: Ca3(PO4)2. In addition, phosphorus compoundsare found in the tissues of various living organisms.
The role of phosphorus and its compounds in nature and the body
This chemical element is very important for the normal functioning of almost all organs and their systems. First of all, without it, the smooth functioning of the kidneys is impossible. This element takes part in the metabolic processes of the body. It also promotes rapid tissue regeneration. Without it, some vitamins simply cannot be activated to benefit the body - which is why phosphorus is often added to almost all vitamin preparations as an additional component. In addition, it is one of the chemical elements that ensure the normal functioning of the heart. He, in addition to all of the above, is involved in the process of cell division, so life on Earth is impossible without this microelement.
Regulation of water-s alt balance is another function that the compounds of the non-metal considered in this article perform in the body. In addition, it is one of the main components of bone and muscle tissue. A large percentage of it is also found in the teeth. Among other things, it is also worth noting that phosphorus is involved in ensuring the normal functioning of the nervous system. The symptoms of a deficiency in the body of the trace element in question are as follows: increased fatigue, low efficiency, disturbances in the functioning of the nervous system (neurosis, hysteria, etc.), too frequent colds, exhaustion of the heart muscle, pain in the bones and muscles, very poor appetite. To avoid such a phenomenon as a lack of phosphorus in the body, you need to knowwhat foods contain it.
First of all, among the products rich in the considered chemical element, fish should be distinguished. A particularly high concentration of phosphorus is observed in species such as sturgeon, mackerel, horse mackerel, tuna, sardine, capelin, pollock, smelt. In addition, the trace element discussed in this article is found in crab meat, shrimp, as well as in dairy products such as cottage cheese, processed cheese, and cheese.
Conclusions
Phosphorus, although not a very common chemical element on the planet, is of great importance both from an industrial and biological point of view. He and his compounds, in particular, phosphorus hydroxide, are used in the manufacture of various kinds of products. The article also described the properties of phosphorus hydroxide (phosphoric acid) and the features of its interaction with metals, bases and s alts.
