Hybridizationis a hypothetical process of mixing different types, but similar in energy, of orbitals of a given atom with the emergence of the same number of new (hybrid 1) orbitals, identical in energy and shape.

Hybridization atomic orbitals occurs during the formation of covalent bonds.

Hybrid orbitals have the shape of a three-dimensional asymmetrical figure eight, strongly elongated to one side of the atomic nucleus: .

This form causes a stronger overlap of hybrid orbitals with the orbitals (pure or hybrid) of other atoms than in the case of pure atomic orbitals and leads to the formation of stronger covalent bonds. Therefore, the energy expended on the hybridization of atomic orbitals is more than compensated by the release of energy due to the formation of stronger covalent bonds involving hybrid orbitals. The name of hybrid orbitals and the type of hybridization are determined by the number and type of atomic orbitals participating in the hybridization, for example: sp-, sp 2 -, sp 3 -, sp 2 d- orsp 3 d 2 -hybridization.

The orientation of the hybrid orbitals, and therefore the geometry of the molecule, depend on the type of hybridization. In practice, the inverse problem is usually solved: first, the geometry of the molecule is established experimentally, after which the type and shape of the hybrid orbitals involved in its formation are described.

sp -Hybridization. Two hybrid sp- As a result of mutual repulsion, the orbitals are located relative to the atomic nucleus in such a way that the angle between them is 180° (Fig. 7).

Rice. 7. Mutual location in space of two sp- hybrid orbitals of one atom: A - surfaces covering regions of space where the probability of an electron being present is 90%; b - conditional image.

As a result of this arrangement of hybrid orbitals, molecules of composition AX 2, where A is the central atom, have linear structure, that is, the covalent bonds of all three atoms are located on the same straight line. For example, in a state sp- hybridization, the valence orbitals of the beryllium atom in the BeCl 2 molecule are located (Fig. 8). Linear configuration due to sp- The molecules BeH 2, Be(CH 3) 2, ZnCl 2, CO 2, HC≡N and a number of others also have hybridization of the valence orbitals of atoms.

Rice. 8. Triatomic linear molecule of beryllium chloride BeC1 2 (in the gaseous state): 1 - 3R- Cl atom orbital; 2 - two sp- hybrid orbitals of the Be atom.

s R 2 -Hybridization. Let us consider the hybridization of one s- and two R- orbitals. In this case, as a result of a linear combination of three orbitals, three hybrid orbitals arise sR 2 -orbitals. They are located in the same plane at an angle of 120° to each other (Fig. 9). sR 2 -Hybridization is characteristic of many compounds of boron, which, as shown above, in the excited state has three unpaired electrons: one s- and two R-electron. When overlapping sR 2 -orbitals of a boron atom with the orbitals of other atoms form three covalent bonds, equal in length and energy. Molecules in which the valence orbitals of the central atom are in the state sR 2 -hybridization, have a triangular configuration. The angles between covalent bonds are 120°. Able sR 2 -hybridization are the valence orbitals of boron atoms in the molecules BF 3, BC1 3, carbon and nitrogen atoms in the anions CO 3 2 -, NO 3 -.

Rice. 9. Mutual position in the space of three sR 2 -hybrid orbitals.

s R 3 -Hybridization. Substances in which the central atom contains four are very widespread. sR 3 -orbitals resulting from a linear combination of one s- and three R-orbitals. These orbitals are located at an angle of 109˚28′ to each other and are directed towards the vertices of the tetrahedron, at the center of which is atomic nucleus(Fig. 10 a).

Formation of four equal covalent bonds due to overlap sR 3 -orbitals with orbitals of other atoms are typical for carbon atoms and other elements of group IVA; this determines the tetrahedral structure of the molecules (CH 4, CC1 4, SiH 4, SiF 4, GeH 4, GeBr 4, etc.).

Rice. 10. The influence of non-bonding electron pairs on the geometry of molecules:

a– methane (no non-bonding electron pairs);

b– ammonia (one non-bonding electron pair);

V– water (two non-bonding pairs).

Lone electron pairs of hybrid orbital lei . In all the examples considered, the hybrid orbitals were “populated” by single electrons. However, there are often cases when a hybrid orbital is “occupied” by an electron pair. This affects the geometry of the molecules. Since a nonbonding electron pair is affected by the nucleus of only its atom, and a bonding electron pair is affected by two atomic nuclei, the nonbonding electron pair is closer to the atomic nucleus than the bonding one. As a result, the nonbonding electron pair repels the bonding electron pairs more than they repel each other. Graphically, for clarity, the large repulsive force acting between the nonbonding and bonding electron pairs can be represented by the larger electron orbital of the nonbonding pair. A non-bonding electron pair is found, for example, on the nitrogen atom in the ammonia molecule (Fig. 10 b). As a result of interaction with bonding electron pairs, the H-N-H bond angles are reduced to 107.78° compared to 109.5° characteristic of a regular tetrahedron.

Bonding electron pairs experience even greater repulsion in a water molecule, where the oxygen atom has two non-bonding electron pairs. As a result, the H-O-H bond angle in a water molecule is 104.5° (Fig. 10 V).

If a non-bonding electron pair, as a result of the formation of a covalent bond through the donor-acceptor mechanism, turns into a bonding one, then the repulsive forces between this bond and other covalent bonds in the molecule are equalized; The angles between these bonds are also aligned. This occurs, for example, during the formation of ammonium cation:

Participation in hybridization d -orbitals. If the energy of atomic d- orbitals are not very different from energies s- And R- orbitals, then they can participate in hybridization. The most common type of hybridization involving d- orbitals is sR 3 d 2 - hybridization, as a result of which six hybrid orbitals of equal shape and energy are formed (Fig. 11 A), located at an angle of 90˚ to each other and directed towards the vertices of the octahedron, in the center of which is the atomic nucleus. Octahedron (Fig. 11 b) – is a regular octahedron: all edges in it are of equal length, all faces are regular triangles.

Rice. eleven. sR 3 d 2 - Hybridization

Less common sR 3 d- hybridization to form five hybrid orbitals (Fig. 12 A), directed to the vertices of the trigonal bipyramid (Fig. 12 b). A trigonal bipyramid is formed by connecting two isosceles pyramids with a common base - a regular triangle. Bold strokes in Fig. 12 b edges of equal length are shown. Geometrically and energetically sR 3 d- hybrid orbitals are unequal: three “equatorial” orbitals are directed towards the vertices regular triangle, and two “axial” ones - up and down perpendicular to the plane of this triangle (Fig. 12 V). The angles between the “equatorial” orbitals are equal to 120°, as with sR 2 - hybridization. The angle between the “axial” and any of the “equatorial” orbitals is 90°. Accordingly, covalent bonds that are formed with the participation of “equatorial” orbitals differ in length and energy from bonds in the formation of which “axial” orbitals participate. For example, in the PC1 5 molecule, the “axial” bonds are 214 pm long, and the “equatorial” bonds are 202 pm long.

Rice. 12. sR 3 d- Hybridization

Thus, considering covalent bonds as a result of overlapping atomic orbitals, it is possible to explain the geometry of the resulting molecules and ions, which depends on the number and type of atomic orbitals involved in the formation of bonds. The concept of hybridization of atomic orbitals, it is necessary to understand that hybridization is a conventional technique that allows you to clearly explain the geometry of a molecule through a combination of AOs.

Problem 261.
What types of carbon AO hybridization correspond to the formation of CH molecules 4, C 2 H 6, C 2 H 4, C 2 H 2?
Solution:
a) In CH molecules 4 and C 2 H 6 The valence electron layer of a carbon atom contains four electron pairs:

Therefore, the electron clouds of the carbon atom in the CH 4 and C 2 H 6 molecules will be maximally distant from each other during sp3 hybridization, when their axes are directed towards the vertices of the tetrahedron. In this case, in the CH4 molecule, all the vertices of the tetrahedron will be occupied by hydrogen atoms, so that the CH4 molecule has a tetrahedral configuration with a carbon atom in the center of the tetrahedron. In the C 2 H 6 molecule, hydrogen atoms occupy three vertices of the tetrahedron, and the common electron cloud of another carbon atom is directed towards the fourth vertex, i.e. two carbon atoms are connected to each other. This can be represented by diagrams:

b) In the C 2 H 4 molecule there is a valence electron layer of the carbon atom, as in the CH 4 and C 2 H 6 molecules. contains four electron pairs:

When C 2 H 4 is formed, three covalent bonds are formed according to the usual mechanism, i.e. are - connections, and one - - connection. When a C 2 H 4 molecule is formed, each carbon atom has two hydrogen atoms - bonds and two bonds to each other, one - and one - bonds. Hybrid clouds that match this type hybridization, are located in the carbon atom so that the interaction between electrons is minimal, i.e. as far apart as possible. This arrangement of carbon atoms (two double bonds between carbon atoms) is characteristic of sp 2 hybridization of carbon AO. During sp 2 hybridization, the electron clouds in carbon atoms are oriented in directions lying in the same plane and making angles of 120 0 with each other, i.e. in directions to the vertices of a regular triangle. In the ethylene molecule, the formation of - bonds involves three sp 2 -hybrid orbitals of each carbon atom, two between two hydrogen atoms and one with the second carbon atom, and - the bond is formed due to the p-electron clouds of each carbon atom. Structural formula molecules C 2 H 4 will look like:

c) In the C 2 H 2 molecule, the valence electron layer of the carbon atom contains four pairs of electrons:

The structural formula of C 2 N 2 is:

Each carbon atom is connected by one electron pair to a hydrogen atom and three electron pairs to another carbon atom. Thus, in an acetylene molecule, carbon atoms are connected to each other by one -bond and two -bonds. Each carbon atom is connected to hydrogen by an - bond. The formation of - bonds involves two sp-hybrid AOs, which are located relative to each other so that the interaction between them is minimal, i.e. as far apart as possible. Therefore, during sp-hybridization, the electron clouds between carbon atoms are oriented in opposite directions relative to each other, i.e. angle between C-C connections is 180 0. Therefore, the C 2 H 2 molecule has a linear structure:

Problem 262.
Indicate the type of hybridization of silicon AO in SiH 4 and SiF 4 molecules. Are these molecules polar?
Solution:
In SiH 4 and SiF 4 molecules, the valence electron layer contains four pairs of electrons:

Therefore, in both cases, the electron clouds of the silicon atom will be maximally distant from each other during sp 3 hybridization, when their axes are directed towards the vertices of the tetrahedron. Moreover, in the SiH 4 molecule all the vertices of the tetrahedron are occupied by hydrogen atoms, and in the SiF 4 molecule - by fluorine atoms, so that these molecules have a tetrahedral configuration with a silicon atom in the center of the tetrahedron:

In tetrahedral molecules SiH 4 and SiF 4, the dipole moments of the Si-H and Si-F bonds mutually cancel each other, so that the total dipole moments of both molecules will be equal to zero. These molecules are non-polar, despite the polarity of the Si-H and Si-F bonds.

Problem 263.
In SO 2 and SO 3 molecules, the sulfur atom is in a state of sp 2 hybridization. Are these molecules polar? What is their spatial structure?
Solution:
During sp 2 hybridization, hybrid clouds are located in the sulfur atom in directions lying in the same plane and making angles of 120 0 with each other, i.e. directed towards the vertices of a regular triangle.

a) In the SO 2 molecule, two sp 2 -hybrid AOs form a bond with two oxygen atoms, the third sp 2 -hybrid orbital will be occupied by a free electron pair. This electron pair will shift the electron plane and the SO 2 molecule will take the shape of an irregular triangle, i.e. angle OSO will not be equal to 120 0. Therefore, the SO 2 molecule will have an angular shape with sp 2 hybridization of the atomic orbitals, the structure:

In the SO 2 molecule, mutual compensation of dipole moments S-O connections not happening; the dipole moment of such a molecule will have a value greater than zero, i.e. the molecule is polar.

b) In the corner SO 3 molecule, all three sp2-hybrid AOs form a bond with three oxygen atoms. The SO3 molecule will have the shape of a flat triangle with sp2 hybridization of the sulfur atom:

In a triangular SO 3 molecule, the dipole moments of the S-O bonds cancel each other out, so that the total dipole moment will be zero, the molecule is polar.

Problem 264.
When SiF4 interacts with HF, a strong acid H 2 SiF 6 is formed, which dissociates into H + and SiF 6 2- ions. Can In a similar way does the reaction occur between CF 4 and HF? Indicate the type of hybridization of silicon AO in the SiF 6 2- ion.
Solution:
a) When excited, the silicon atom goes from the 1s 2 2s 2 2p 6 3s 2 3p 3 state to the 1s 2 2s 2 2p 6 3s 1 3p 4 3d 0 state, and the electronic structure of the valence orbitals corresponds to the scheme:

Four unpaired electrons of an excited silicon atom can participate in the formation of four covalent bonds according to the usual mechanism with fluorine atoms (1s 2 2s 2 2p 5), each having one unpaired electron, to form a SiF 4 molecule.

When SiF 4 interacts with HF, the acid H 2 SiF 6 is formed. This is possible because the SiF 4 molecule has free 3d orbitals, and the F- (1s 2 2s 2 2p 6) ion has free pairs of electrons. The connection is carried out according to the donor-acceptor mechanism due to a pair of electrons from each of the two ions F - (HF ↔ H + + F -) and free 3d orbitals of the SiF 4 molecule. In this case, the SiF 6 2- ion is formed, which with the H + ions forms an acid molecule H 2 SiF 6.

b) Carbon (1s 2 2s 2 2p 2) can form, like silicon, a CF 4 compound, but the valence capabilities of the carbon atom will be exhausted (there are no unpaired electrons, free pairs of electrons and free valence orbitals at the valence level). The structure diagram of the valence orbitals of an excited carbon atom has the form:

When CF 4 is formed, all valence orbitals of carbon are occupied, so an ion cannot be formed.

In the SiF 4 molecule, the valence electron layer of the silicon atom contains four pairs of electrons:

The same is observed for the CF 4 molecule. therefore, in both cases, the electron clouds of silicon and carbon atoms will be as far apart as possible from each other during sp3 hybridization. When their axes are directed to the vertices of the tetrahedron:

Continuation. See the beginning in № 15, 16/2004

Lesson 5. Hybridization
carbon atomic orbitals

A covalent chemical bond is formed using shared bonding electron pairs like:

Form a chemical bond, i.e. Only unpaired electrons can create a common electron pair with a “foreign” electron from another atom. When writing electronic formulas, unpaired electrons are located one at a time in an orbital cell.
Atomic orbital is a function that describes the density of the electron cloud at each point in space around the atomic nucleus. An electron cloud is a region of space in which an electron can be detected with a high probability.
To harmonize the electronic structure of the carbon atom and the valence of this element, concepts about the excitation of the carbon atom are used. In the normal (unexcited) state, the carbon atom has two unpaired 2 R 2 electrons. IN excited state(when absorbing energy) one of 2 s 2 electrons can go to free R-orbital. Then four unpaired electrons appear in the carbon atom:

Let us recall that in the electronic formula of an atom (for example, for carbon 6 C – 1 s 2 2s 2 2p 2) large numbers in front of the letters - 1, 2 - indicate the number of the energy level. Letters s And R indicate the shape of the electron cloud (orbital), and the numbers to the right above the letters indicate the number of electrons in a given orbital. All s-spherical orbitals:

At the second energy level except 2 s-there are three orbitals 2 R-orbitals. These 2 R-orbitals have an ellipsoidal shape, similar to dumbbells, and are oriented in space at an angle of 90° to each other. 2 R-Orbitals denote 2 p x, 2p y and 2 p z in accordance with the axes along which these orbitals are located.

When chemical bonds are formed, the electron orbitals acquire the same shape. Thus, in saturated hydrocarbons one s-orbital and three R-orbitals of the carbon atom to form four identical (hybrid) sp 3-orbitals:

This - sp 3 -hybridization.
Hybridization– alignment (mixing) of atomic orbitals ( s And R) with the formation of new atomic orbitals called hybrid orbitals.

Hybrid orbitals have an asymmetric shape, elongated towards the attached atom. Electron clouds repel each other and are located in space as far as possible from each other. In this case, the axes of four sp 3-hybrid orbitals turn out to be directed towards the vertices of the tetrahedron (regular triangular pyramid).
Accordingly, the angles between these orbitals are tetrahedral, equal to 109°28".
Peaks electron orbitals may overlap with the orbitals of other atoms. If electron clouds overlap along a line connecting the centers of atoms, then such a covalent bond is called sigma()-connection. For example, in the ethane molecule C 2 H 6, a chemical bond is formed between two carbon atoms by overlapping two hybrid orbitals. This is a connection. In addition, each of the carbon atoms with its three sp 3-orbitals overlap with s-orbitals of three hydrogen atoms, forming three -bonds.

In total, three valence states are possible for a carbon atom with different types hybridization. Except sp 3-hybridization exists sp 2 - and sp-hybridization.
sp 2 -Hybridization- mixing one s- and two R-orbitals. As a result, three hybrids are formed sp 2 -orbitals. These sp 2-orbitals are located in the same plane (with axes X, at) and are directed to the vertices of the triangle with an angle between the orbitals of 120°. Unhybridized
R-the orbital is perpendicular to the plane of the three hybrid sp 2-orbitals (oriented along the axis z). Upper half R-the orbital is above the plane, bottom half- below the plane.
Type sp 2-carbon hybridization occurs in compounds with a double bond: C=C, C=O, C=N. Moreover, only one of the bonds between two atoms (for example, C=C) can be an - bond. (The other bonding orbitals of the atom are directed in opposite directions.) The second bond is formed as a result of overlapping non-hybrid R-orbitals on both sides of the line connecting the atomic nuclei.

Covalent bond formed by lateral overlap R-orbitals of neighboring carbon atoms is called pi()-connection.

Education -communications

Due to less orbital overlap, the -bond is less strong than the -bond.
sp-Hybridization– this is mixing (alignment in shape and energy) of one s- and one
R-orbitals to form two hybrid sp-orbitals. sp-The orbitals are located on the same line (at an angle of 180°) and directed in opposite directions from the nucleus of the carbon atom. Two
R-orbitals remain unhybridized. They are placed mutually perpendicular
directions of connections. On the image sp-orbitals are shown along the axis y, and the unhybridized two
R-orbitals – along the axes X And z.

A carbon-carbon triple bond CC consists of an -bond formed by overlapping
sp-hybrid orbitals, and two -bonds.
The relationship between such parameters of the carbon atom as the number of attached groups, the type of hybridization and the types of chemical bonds formed is shown in Table 4.

Table 4

Covalent carbon bonds

Number of groups related with carbon	Type hybridization	Types participating chemical bonds	Examples of compound formulas
4	sp 3	Four - connections
3	sp 2	Three - connections and one - connection
2	sp	Two - connections and two - connections	H–CC–H

Exercises.

1. Which electrons of atoms (for example, carbon or nitrogen) are called unpaired?

2. What does the concept of “shared electron pairs” mean in compounds with a covalent bond (for example, CH 4 or H 2 S )?

3. What electronic states of atoms (for example, C or N ) are called basic, and which are excited?

4. What do the numbers and letters mean in the electronic formula of an atom (for example, C or N )?

5. What is an atomic orbital? How many orbitals are there in the second energy level of the C atom? and how do they differ?

6. How are hybrid orbitals different from the original orbitals from which they were formed?

7. What types of hybridization are known for the carbon atom and what do they consist of?

8. Draw a picture of the spatial arrangement of orbitals for one of the electronic states of the carbon atom.

9. What chemical bonds are called and what? Specify-And-connections in connections:

10. For the carbon atoms of the compounds below, indicate: a) type of hybridization; b) types of its chemical bonds; c) bond angles.

Answers to exercises for topic 1

Lesson 5

1. Electrons that are located one at a time in an orbital are called unpaired electrons. For example, in the electron diffraction formula of an excited carbon atom there are four unpaired electrons, and the nitrogen atom has three:

2. Two electrons involved in the formation of one chemical bond are called shared electron pair. Typically, before a chemical bond is formed, one of the electrons in this pair belonged to one atom, and the other electron belonged to another atom:

3. Electronic state of an atom in which the order of filling electron orbitals is observed: 1 s 2 , 2s 2 , 2p 2 , 3s 2 , 3p 2 , 4s 2 , 3d 2 , 4p 2, etc., are called underlying condition. IN excited state one of the valence electrons of the atom occupies a free orbital with a higher energy; such a transition is accompanied by the separation of paired electrons. Schematically it is written like this:

While in the ground state there were only two unpaired valence electrons, in the excited state there are four such electrons.

5. An atomic orbital is a function that describes the density of the electron cloud at each point in space around the nucleus of a given atom. At the second energy level of the carbon atom there are four orbitals - 2 s, 2p x, 2p y, 2p z. These orbitals differ:
a) the shape of the electron cloud ( s– ball, R– dumbbell);
b) R-orbitals have different orientations in space - along mutually perpendicular axes x, y And z, they are designated p x, p y, p z.

6. Hybrid orbitals differ from the original (non-hybrid) orbitals in shape and energy. For example, s-orbital – the shape of a sphere, R– symmetrical figure eight, sp-hybrid orbital – asymmetric figure eight.
Energy differences: E(s) < E(sp) < E(R). Thus, sp-orbital – an orbital averaged in shape and energy, obtained by mixing the original s- And p-orbitals.

7. For a carbon atom, three types of hybridization are known: sp 3 , sp 2 and sp (see text of lesson 5).

9. -bond - a covalent bond formed by head-on overlapping of orbitals along a line connecting the centers of atoms.
-bond – a covalent bond formed by lateral overlap R-orbitals on both sides of the line connecting the centers of the atoms.
-Bonds are shown by the second and third lines between connected atoms.

Sp-hybridization

sp-hybridization occurs, for example, during the formation of Be, Zn, Co and Hg (II) halides. In the valence state, all metal halides contain s and p-unpaired electrons at the appropriate energy level. When a molecule is formed, one s and one p orbital form two hybrid sp orbitals at an angle of 180 degrees.

Fig.3 sp hybrid orbitals

Experimental data show that Be, Zn, Cd and Hg(II) halides are all linear and both bonds are of the same length.

sp 2 hybridization

As a result of the hybridization of one s-orbital and two p-orbitals, three hybrid sp 2 orbitals are formed, located in the same plane at an angle of 120 o to each other. This is, for example, the configuration of the BF 3 molecule:

Fig.4 sp 2 hybridization

sp 3 hybridization

sp 3 hybridization is characteristic of carbon compounds. As a result of the hybridization of one s orbital and three

p-orbitals, four hybrid sp 3 orbitals are formed, directed towards the vertices of the tetrahedron with an angle between the orbitals of 109.5 o. Hybridization is manifested in the complete equivalence of the bonds of a carbon atom with other atoms in compounds, for example, in CH 4, CCl 4, C(CH 3) 4, etc.

Fig.5 sp 3 hybridization

If all hybrid orbitals are connected to the same atoms, then the bonds are no different from each other. In other cases, slight deviations from standard bond angles occur. For example, in the water molecule H 2 O, oxygen - sp 3 -hybrid, is located in the center of an irregular tetrahedron, at the vertices of which two hydrogen atoms and two lone pairs of electrons “look” (Fig. 2). The shape of the molecule is angular when viewed from the centers of the atoms. The HOH bond angle is 105°, which is quite close to the theoretical value of 109°.

Fig.6 sp 3 - hybridization of oxygen and nitrogen atoms in molecules a) H 2 O and b) NCl 3.

If there were no hybridization (“alignment” O-H bonds), the bond angle of HOH would be 90° because the hydrogen atoms would be attached to two mutually perpendicular p orbitals. In this case, our world would probably look completely different.

The hybridization theory explains the geometry of the ammonia molecule. As a result of the hybridization of the 2s and three 2p orbitals of nitrogen, four sp 3 hybrid orbitals are formed. The configuration of the molecule is a distorted tetrahedron, in which three hybrid orbitals participate in the formation of a chemical bond, but the fourth with a pair of electrons does not. Angles between N-H bonds not equal to 90° as in a pyramid, but also not equal to 109.5°, corresponding to a tetrahedron.

Fig.7 sp 3 - hybridization in an ammonia molecule

When ammonia interacts with a hydrogen ion, as a result of donor-acceptor interaction, an ammonium ion is formed, the configuration of which is a tetrahedron.

Hybridization also explains the difference in angle between O-H connections in the corner water molecule. As a result of the hybridization of the 2s and three 2p orbitals of oxygen, four sp 3 hybrid orbitals are formed, of which only two are involved in the formation of a chemical bond, which leads to a distortion of the angle corresponding to the tetrahedron.

Fig.8 sp 3 hybridization in a water molecule

Hybridization can involve not only s- and p-orbitals, but also d- and f-orbitals.

With sp 3 d 2 hybridization, 6 equivalent clouds are formed. It is observed in such compounds as 4-, 4-. In this case, the molecule has an octahedron configuration.

We hear a lot about hybrids. Films and books talk about them, and science also examines them. In the first two sources, hybrids are very dangerous creatures. They can bring a lot of evil. But hybridization is not always a bad thing. Quite often it is good.

An example of hybridization is every person. We are all hybrids of two people - father and mother. Thus, the fusion of an egg and a sperm is also a kind of hybridization. It is this mechanism that allows evolution to move forward. In this case, hybridization also occurs with negative sign. let's consider this phenomenon generally.

General idea of ​​hybridization

However, not only biology includes this concept. And let the introduction consider an example with hybrids as full-fledged individuals of an incomprehensible biological species. Moreover, this concept can be used in other sciences. And the meaning of this term will be slightly different. But at the same time, there is still something in common. It is the word "union" that unites everything possible values of this term.

Where does this concept exist?

The term "hybridization" is used in a number of sciences. And since most of existing disciplines overlap, then we can safely talk about the use of each meaning of this term in any science, one way or another connected with natural research fields. At the same time, this term is most actively used in:

1. Biology. This is where the concept of hybrid comes from. Although, as always, when moving from science to daily life there was some misrepresentation of facts. By hybrid we mean an individual resulting from crossing two other species. Although this does not always happen.
2. Chemistry. This concept means the mixing of several orbitals - unique paths of electron motion.
3. Biochemistry. The key concept here is DNA hybridization.

As you can see, the third point is at the junction of two sciences. And this is absolutely normal practice. The same term can form a completely different meaning at the junction of two sciences. Let's take a closer look at the concept of hybridization in these sciences.

What is a hybrid?

A hybrid is a creature that is created through the process of hybridization. This concept relates to biology. Hybrids can be obtained either accidentally or on purpose. In the first case, these can be animals that are created in the process of mating two different species of creatures.

For example, they talk about cats and dogs having children who are neither of them. Sometimes hybrids are created on purpose. For example, when a cherry is attached to an apricot, we are dealing with a special hybridization.

Hybridization in biology

Biology - interesting science. And the concept of hybridization is no less fascinating. This term refers to the combination of genetic material different cells one. These can be representatives of one species or several. Accordingly, there is a division into such types of hybridization.

• Intraspecific hybridization. This is when two individuals of the same species create an offspring. An example of intraspecific hybridization is humans. It was obtained through the process of fusion of germ cells of representatives of one biological species.
• Interspecific hybridization. This is when similar, but belonging to different species, animals are crossed. For example, a hybrid of a horse and a zebra.
• Distant hybridization. This is when representatives of at least the same species interbreed, but are not united by family ties.

Each of these varieties helps not only evolution. Scientists are also actively trying to crossbreed different types Living creatures. It works best with plants. There are several reasons for this:

• Different number of chromosomes. Each species has not only a specific number of chromosomes, but also a set of them. All this interferes with the reproduction of offspring.
• Only hybrid plants can reproduce. And that's not always the case.
• Only plants can be polyploid. For a plant to reproduce, it must become polyploid. In the case of animals, this is certain death.
• Possibility of vegetative hybridization. It's very simple and convenient way creating hybrids of several plants.

These are the reasons why crossing two plants is much easier and more effective. In the case of animals, it may be possible to achieve the possibility of reproduction in the future. But on this moment The official opinion in biology is that hybrid animals lose the ability to reproduce, since these individuals are genetically unstable. Therefore, it is unknown what their reproduction may lead to.

Types of hybridization in biology

Biology is a fairly broad science in its specialization. There are two types of hybridization that it provides:

1. Genetic. This is when two cells are made into one with a unique set of chromosomes.
2. Biochemical. An example of this type is DNA hybridization. This is when complementary nucleic acids combine to form one DNA.

Can be divided into more varieties. But we did this in the previous subsection. Thus, distant and intraspecific hybridization are components of the first type. And there the classification expands even further.

The concept of vegetative hybridization

Vegetative hybridization is a concept in biology that means a type of crossing of two plants in which part of one species takes root on another. That is, hybridization occurs due to the combination of two different parts body. Yes, this is how you can characterize a plant. After all, he also has his own organs, united into a whole system. Therefore, if you call a plant an organism, there is nothing wrong with that.

Vegetative hybridization has a number of advantages. This:

• Convenience.
• Simplicity.
• Efficiency.
• Practicality.

These advantages make this type of crossbreeding very popular among gardeners. There is also such a thing as somatic hybridization. This is when not germ cells are crossed, but somatic cells, or rather, their protoplasts. This method Crossing is carried out when it is impossible to create a hybrid by standard sexual means between several plants.

Hybridization in chemistry

But now we will step back a little from biology and talk about another science. Chemistry has its own concept, it is called “hybridization of atomic orbitals.” This is very complex term, but if you understand a little chemistry, then there is nothing complicated about it. First we need to explain what an orbital is.

This is a kind of path along which the electron moves. We were taught this at school. And if it happens that these orbitals different types mixed, a hybrid is obtained. There are three types of phenomenon called "orbital hybridization". These are the following varieties:

• sp hybridization - one s and the other p orbital;
• sp 2 hybridization - one s and two p orbitals;
• sp 3 hybridization - one s and three p orbitals are combined.

This topic is quite complex to study, and it must be considered inseparably from the rest of the theory. Moreover, the concept of orbital hybridization concerns more the end of this topic, rather than the beginning. After all, you need to study the very concept of orbitals, what they are, and so on.

conclusions

So, we have understood the meaning of the concept of “hybridization”. This turns out to be quite interesting. For many, it was a discovery that chemistry also has this concept. But if such people did not know this, then what could they learn? And so, there is development. It is important not to stop training your erudition, as this will definitely characterize you on the good side.