Hello dear children and parents! Sometimes the television news shows not very pleasant stories about earthquakes that have occurred in the world. Usually the picture on the TV screen strikes with its terrifying character: destroyed houses, tears of people, bitterness of loss. Why is Mother Nature so offended by us and is it possible to prevent something if you know why an earthquake occurs? Let's try to figure it out.

This information will assist you in the preparation of project research work dedicated to this terrible and dangerous natural phenomenon.

Lesson plan:

What is an earthquake?

Briefly describe a natural phenomenon, then an earthquake is tremors and the movement of the Earth's surface. These fluctuations are destructive in nature and occur suddenly, without much warning.

A natural disaster can occur in any country and at any time of the year, its geography is wide. In the process of an earthquake, the earth's crust is torn, and some of its sections are displaced, which often leads to the destruction of cities, and sometimes even entire civilizations are erased from the Earth.

Every year, hundreds of thousands of earthquakes occur in the world, only many of them go unnoticed by ordinary people. They are fixed only by specialists with the help of special equipment. Only the strongest shocks and changes earth's surface leave an imprint on people.

No one has seen earthquakes that take place at the bottom of the oceans, because their action is extinguished by water. If the shocks from the ocean are too strong, they give rise to giant waves that wash away everything in their path.

Natural causes of earthquakes

Tremors can occur on the initiative of nature, without human intervention.

Tectonic movement

This is due to the so-called tectonic shifts somewhere deep in earth's crust. Surface the globe not so motionless as it seems to us at first glance, such as, for example, the tabletop at the table. It consists of lithospheric plates that are slowly but constantly shifting at a rate of no more than 7 centimeters per year.

This movement is explained by the fact that viscous magma boils in the bowels of the planet Earth, and the plates float on it, like ice floes along a river during an ice drift. Where the plates touch, their surfaces deform. You have seen the consequences of this with your own eyes. Yes, don't be surprised! Have you never seen mountains?

But when two or more lithospheric plates they rub against each other and cannot agree and divide the space in any way, they cling and argue, their movement is suspended. They can quarrel so strongly among themselves that, pressing against each other with strong energy, they lead to a shock wave, swelling and breaking the surface.

These moments are the beginning of the earthquake. Such a lithospheric quarrel can spread its force over hundreds and thousands of kilometers, causing vibrations of the earth's surface.

What is the impetus for tectonic movement? Scientists have found several explanations for this phenomenon. The state of the Earth's surface is affected by the cosmos that we have not quite studied and a star called the Sun, which bring magnetic storms and bright solar flares.

The culprit of earthquakes may be the Moon, or rather, the changes that occur on the lunar surface. Experts have noticed that the most powerful earthquakes occur at night, during the full moon.

Impact of volcanoes, landslides and water

In addition to tectonic shifts, which bring the most devastating damage, scientists see another reason for the earthquake in volcanoes, landslides and collapses.

The former are terrible for their overvoltage due to the concentration of volcanic gas and lava in the bowels, as a result of which seismic waves appear during the eruption, which are felt on Earth.

The second are dangerous shock wave from the gathering of a heavy mass rocks to the earth's surface.

There are also failure earthquakes of small impact, when groundwater erodes certain parts of the surface so much that the sections fall inward, causing seismic vibrations.

Man's fault in the occurrence of earthquakes

Unfortunately, not only mother nature can cause earthquakes. A person with his own hands creates such a situation when the planet begins to resent.

Of course, the strength of such man-made shocks (namely, this is how disasters are called, the source of which is a person) is not high, but they can lead to fluctuations in the earth's surface.

How is the strength of earthquakes measured?

How strong the tremors can be measured with special instruments - seismographs.

They determine the magnitude of earthquakes and make up a scale, the most famous of which is called the Richter.

A force of 1 or 2 points is not felt by a person, but fluctuations of 3 or 4 points are already swaying the surrounding interior items - dishes begin to ring, lamps on the ceiling stagger. When the strength of the shocks reaches 5 points, cracks begin to appear on the room walls and plaster crumbles, after 6-7 indicators, not only the room partitions, but also the stone walls of the buildings themselves are destroyed.

If seismographs fix values ​​​​of 8-10 points, bridges, roads, houses do not withstand the onslaught, cracks appear on the surface of the Earth, pipelines break through, railway rails are damaged. The greatest damage is caused by earthquakes with tremors of more than 10 points, which change the landscape, wipe entire cities off the face of the Earth, turning them into ruins, dips appear in the earth, and new islands may appear in the sea.

The Richter scale can fix a maximum of 10 points, for stronger shocks, another one is used - Mercalli, which has 12 levels. There is another one - the Medvedev-Sponheuer-Karnik scale, which was previously used in the Soviet Union. It is also designed for 12 divisions.

Most often, earthquakes occur in the Mediterranean belt, passing through the Himalayas, Altai, the Caucasus, as well as in the Pacific belt, affecting Japan, Hawaii, Chile and even Antarctica.

There are also seismically active zones on the territory of our country - for example, Chukotka, Primorye, Baikal and Kamchatka. Neighbors such as Kazakhstan, Armenia and Kyrgyzstan also often experience natural disasters.

In August 2016, a 6.1 magnitude earthquake in Italy claimed the lives of dozens of people, many were missing.

According to scientists, today there is no such country that would not be threatened by earthquakes. In the south of Europe, these are Portugal, Spain, Greece. In the north of Europe in Atlantic Ocean there is a restless ridge that reaches the very Arctic Ocean. Under our native capital, as studies show, there is no active plate movement, but experts say that this is not a reason for Muscovites to calm down.

There is also no reason to calm down among the inhabitants of the country. rising sun. Japan has over 1,000 earthquakes a year. One of them, which happened on March 11, 2011, was on the news all over the world. You will find shocking footage and details of this natural disaster on the video.

Now you know why such a natural disaster as an earthquake occurs. Unfortunately, even with information about the impending danger, a person fails to prevent natural disasters.

See you soon on new topics!

Evgenia Klimkovich.

In chemistry and physics, atomic orbitals are a function called a wave orbital that describes the properties that are characteristic of no more than two electrons in a neighborhood, or a system of nuclei, as in a molecule. An orbital is often depicted as a three-dimensional region within which there is a 95 percent chance of finding an electron.

Orbitals and Orbits

As a planet moves around the sun, it traces a path called an orbit. In a similar way an atom can be represented as electrons circling in orbits around the nucleus. In fact, things are different, and the electrons are in regions of space known as atomic orbitals. Chemistry is content with a simplified model of the atom to calculate the Schrödinger wave equation and, accordingly, determine the possible states of the electron.

Orbits and orbitals sound similar, but they have completely different meanings. It is extremely important to understand the difference between them.

Impossibility of depicting orbits

To plot the trajectory of something, one must know exactly where the object is and be able to ascertain where it will be in a moment. For an electron, this is impossible.

According to one cannot know exactly where the particle is at the moment and where it will be later. (In fact, the principle says that it is impossible to determine simultaneously and with absolute accuracy its momentum and momentum).

Therefore, it is impossible to construct an orbit of the electron around the nucleus. Does this big problem? No. If something is not possible, it should be accepted and ways around it should be found.

Hydrogen electron - 1s orbital

Suppose there is one hydrogen atom and at a certain point in time, the position of one electron is graphically imprinted. Shortly thereafter, the procedure is repeated and the observer finds that the particle is in a new position. How she got from the first place to the second is unknown.

If you continue to act in this way, then a kind of 3D map of the places where the particle is likely to be will gradually form.

In the case, the electron can be located anywhere within the spherical space surrounding the nucleus. The diagram shows a cross section of this spherical space.

95% of the time (or any other percentage, since only the size of the universe can provide absolute certainty) the electron will be within a fairly easily defined region of space, close enough to the nucleus. Such a region is called an orbital. Atomic orbitals are regions of space in which an electron exists.

What is he doing there? We don't know, we can't know, and therefore we simply ignore this problem! We can only say that if an electron is in a particular orbit, then it will have a certain energy.

Each orbital has a name.

The space occupied by the hydrogen electron is called the 1s orbital. The unit here means that the particle is at the energy level closest to the nucleus. S tells about the shape of the orbit. S-orbitals are spherically symmetrical about the nucleus - at least like a hollow ball of fairly dense material with a nucleus at its center.

2s

The next orbital is 2s. It is similar to 1s, except that the electron's most likely location is farther from the nucleus. This is the second energy level orbital.

If you look closely, you will notice that closer to the core there is another region somewhat larger. high density electron ("density" is another way of referring to the probability that this particle is present in a certain place).

2s electrons (and 3s, 4s, etc.) spend some of their time much closer to the center of the atom than one might expect. The result of this is a slight decrease in their energy in s-orbitals. The closer the electrons get to the nucleus, the lower their energy becomes.

3s-, 4s-orbitals (and so on) are located further and further from the center of the atom.

p-orbitals

Not all electrons inhabit s orbitals (in fact, very few of them do). On the first, the only available location for them is 1s, on the second, 2s and 2p are added.

Orbitals of this type are more like 2 identical balloons, connected to each other at the core. The diagram shows a cross section of a 3-dimensional region of space. Again, the orbital only shows the area with a 95 percent chance of finding a single electron.

If we imagine a horizontal plane that passes through the nucleus in such a way that one part of the orbit will be above the plane and the other below it, then there is a zero probability of finding an electron on this plane. So how does a particle get from one part to another if it can never pass through the plane of the nucleus? This is due to its wave nature.

Unlike the s-, p-orbital has a certain directionality.

At any energy level, it is possible to have three absolutely equivalent p-orbitals located at right angles to each other. They are arbitrarily denoted by the symbols p x, p y and p z . This is accepted for convenience - what is meant by the directions X, Y or Z is constantly changing, since the atom randomly moves in space.

P-orbitals at the second energy level are called 2p x, 2p y and 2p z. There are similar orbitals on the subsequent ones - 3p x, 3p y, 3p z, 4p x, 4p y, 4p z and so on.

All levels, with the exception of the first, have p-orbitals. At higher levels, the "petals" are more elongated, with the most likely location of the electron at a greater distance from the nucleus.

d- and f-orbitals

In addition to the s and p orbitals, there are two other sets of orbitals available to electrons for more than high levels energy. On the third, there may be five d-orbitals (with complex shapes and names), as well as 3s- and 3p-orbitals (3p x , 3p y , 3p z). There are 9 in total here.

On the fourth, along with 4s and 4p and 4d, 7 additional f-orbitals appear - 16 in total, also available at all higher energy levels.

Placement of electrons in orbitals

An atom can be thought of as a very fancy house (like an inverted pyramid) with a nucleus living on the ground floor and various rooms on the upper floors occupied by electrons:

• on the first floor there is only 1 room (1s);
• on the second room there are already 4 (2s, 2p x, 2p y and 2p z);
• on the third floor there are 9 rooms (one 3s, three 3p and five 3d orbitals) and so on.

But the rooms are not very big. Each of them can only contain 2 electrons.

A convenient way to show the atomic orbitals that these particles are in is to draw "quantum cells".

quantum cells

Atomic orbitals can be represented as squares with the electrons in them shown as arrows. Often, up and down arrows are used to show that these particles are different from each other.

The need for different electrons in an atom is a consequence of quantum theory. If they're in different orbitals, that's fine, but if they're in the same orbit, then there must be some subtle difference between them. Quantum theory endows the particles with a property called "spin" - it is this that denotes the direction of the arrows.

A 1s orbital with two electrons is shown as a square with two arrows pointing up and down, but it can also be written even faster as 1s 2 . It reads "one s two", not "one s squared". The numbers in these notations should not be confused. The first is the energy level, and the second is the number of particles per orbital.

Hybridization

In chemistry, hybridization is the concept of mixing atomic orbitals into new hybrid orbitals capable of pairing electrons to form chemical bonds. Sp hybridization explains chemical bonds compounds such as alkynes. In this model, the 2s and 2p carbon atomic orbitals mix to form two sp orbitals. Acetylene C 2 H 2 consists of an sp-sp entanglement of two carbon atoms with the formation of a σ-bond and two additional π-bonds.

The atomic orbitals of carbon in saturated hydrocarbons have the same hybrid sp 3 -orbitals, having the shape of a dumbbell, one part of which is much larger than the other.

Sp 2 hybridization is similar to the previous ones and is formed by mixing one s and two p orbitals. For example, in an ethylene molecule, three sp 2 - and one p-orbital are formed.

Atomic orbitals: filling principle

Imagine transitions from one atom to another in periodic table chemical elements, one can establish the electronic structure of the next atom by placing an extra particle in the next available orbital.

Electrons, before filling the higher energy levels, occupy the lower ones located closer to the nucleus. Where there is a choice, they fill the orbitals individually.

This filling order is known as Hund's rule. It only applies when the atomic orbitals have equal energies, and it also helps to minimize repulsion between electrons, making the atom more stable.

Note that the s orbital always has slightly less energy than the p orbital at the same energy level, so the former always fill up before the latter.

What is really strange is the position of the 3d orbitals. They are at a higher level than 4s, and so the 4s orbitals fill up first, followed by all the 3d and 4p orbitals.

The same confusion occurs at higher levels with more interweaving between them. Therefore, for example, the 4f atomic orbitals are not filled until all the places on 6s are occupied.

Knowing the order of filling is central to understanding how to describe electronic structures.

m quantum numbers.

The wave function is calculated according to the Schrödinger wave equation within the one-electron approximation (the Hartree-Fock method) as the wave function of an electron in a self-consistent field created by the atomic nucleus with all other electrons of the atom.

E. Schrodinger himself considered an electron in an atom as a negatively charged cloud, the density of which is proportional to the square of the value of the wave function at the corresponding point of the atom. In this form, the concept of an electron cloud was also perceived in theoretical chemistry.

However, most physicists did not share E. Schrödinger's beliefs - there was no evidence of the existence of an electron as a "negatively charged cloud". Max Born substantiated the probabilistic interpretation of the square of the wave function. In 1950, E. Schrödinger in the article “What is elementary particle? forced to agree with the arguments of M. Born, who in 1954 was awarded Nobel Prize in physics with the wording "For fundamental research in quantum mechanics, especially for the statistical interpretation of the wave function."

Quantum numbers and orbital nomenclature

Radial probability density distribution for atomic orbitals for various n and l.

• Principal quantum number n can take any positive integer values, starting from one ( n= 1,2,3, … ∞) and determines the total energy of an electron in a given orbital (energy level):

Energy for n= ∞ corresponds to the single-electron ionization energy for the given energy level.

• The orbital quantum number (also called the azimuthal or complementary quantum number) determines the angular momentum of an electron and can take integer values ​​from 0 to n - 1 (l = 0,1, …, n- one). The angular momentum in this case is given by the relation

Atomic orbitals are called letter designation their orbital number:

The letter designations of atomic orbitals originated from the description of spectral lines in atomic spectra: s (sharp) is a sharp series in atomic spectra, p (principal)- home, d (diffuse) - diffuse, f (Fundamental) is fundamental.

• Magnetic quantum number m l determines the projection of the orbital angular momentum on the direction magnetic field and can take integer values ​​ranging from - l before l, including 0 ( m l = -l … 0 … l):

In the literature, orbitals are denoted by a combination of quantum numbers, with the principal quantum number denoted by a number, the orbital quantum number by the corresponding letter (see table below) and the magnetic quantum number by a subscript expression showing the projection of the orbital onto the Cartesian axes x, y, z, for example 2p x, 3d xy, 4f z(x²-y²). For orbitals of the outer electron shell, that is, in the case of describing valence electrons, the main quantum number in the record of the orbital, as a rule, is omitted.

Geometric representation

The geometric representation of an atomic orbital is a region of space bounded by a surface of equal density (equidensity surface) of probability or charge. The probability density on the boundary surface is chosen based on the problem being solved, but usually in such a way that the probability of finding an electron in a limited area lies in the range of 0.9-0.99.

Since the energy of an electron is determined by the Coulomb interaction and, consequently, by the distance from the nucleus, the main quantum number n sets the size of the orbital.

The shape and symmetry of the orbital are given by the orbital quantum numbers l and m: s-orbitals are spherically symmetrical, p, d and f-orbitals have a more complex shape, determined by the angular parts of the wave function - the angular functions. Angular functions Y lm (φ , θ) - eigenfunctions of the squared angular momentum operator L², depending on quantum numbers l and m(see Spherical functions), are complex and describe in spherical coordinates (φ, θ) the angular dependence of the probability of finding an electron in the central field of an atom. The linear combination of these functions determines the position of the orbitals relative to the Cartesian coordinate axes.

For linear combinations Y lm the following notation is accepted:

The value of the orbital quantum number	0	1	1	1	2	2	2	2	2
The value of the magnetic quantum number	0	0			0
Linear Combination
Designation

An additional factor, sometimes taken into account in the geometric representation, is the sign of the wave function (phase). This factor is essential for orbitals with an orbital quantum number l, different from zero, that is, not having spherical symmetry: the sign of the wave function of their "petals" lying on opposite sides of the nodal plane is opposite. The sign of the wave function is taken into account in the MO LCAO molecular orbital method (molecular orbitals as a linear combination of atomic orbitals). Today, science knows the mathematical equations that describe geometric figures, representing orbitals (depending on the electron coordinates on time). These are the equations harmonic vibrations reflecting the rotation of particles in all available degrees of freedom - orbital rotation, spin,... The hybridization of orbitals is represented as the interference of oscillations.

The filling of orbitals with electrons and the electronic configuration of the atom

Each orbital can have no more than two electrons, differing in the value of the spin quantum number s(back). This prohibition is determined by the Pauli principle. The order in which electrons fill orbitals of the same level (orbitals with the same value of the principal quantum number n) is determined by the Klechkovsky rule, the order in which electrons fill orbitals within the same sublevel (orbitals with the same values ​​of the principal quantum number n and orbital quantum number l) is determined by Hund's Rule.

A brief record of the distribution of electrons in an atom over various electron shells of the atom, taking into account their principal and orbital quantum numbers n and l called

The electron has a dual nature: in different experiments, it can exhibit the properties of a particle and a wave. Properties of an electron as a particle: mass, charge; wave properties- in the features of movement, interference and diffraction.

The motion of an electron obeys the laws quantum mechanics .

The main characteristics that determine the movement of an electron around the nucleus: energy and spatial features of the corresponding orbital.

When interacting (overlapping) atomic orbitals(AO ) belonging to two or more atoms are formed molecular orbitals(MO).

Molecular orbitals are filled with socialized electrons and carry out covalent bond.

Before the formation of molecular orbitals, hybridization of atomic orbitals of one atom.

Hybridization - change in the shape of some orbitals during the formation covalent bond for more efficient coverage. The same hybrids are formed JSC who are involved in education MO, overlapping the atomic orbitals of other atoms. Hybridization is possible only for atoms that form chemical bonds, but not for free atoms.

hydrocarbons

Main questions:

1. Hydrocarbons. Classification. Nomenclature.
2. Structure. Properties.
3. The use of hydrocarbons.

hydrocarbons- Class organic compounds which are made up of two elements: carbon and hydrogen.

Choose isomers and homologues:

Name alkanes:

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Ä nitration reaction (Konovalov's reaction, 1889) is the reaction of substitution of hydrogen for a nitro group.

Terms: 13% HNO 3, t \u003d 130 - 140 0 C, P \u003d 15 - 10 5 Pa. On an industrial scale, the nitration of alkanes is carried out in the gas phase at 150 - 170 0 C with nitric oxide (IV) or nitric acid vapor.

CH 4 + HO - NO 2 → CH 3 - NO 2 + H 2 O

nitromethane

@ Solve tasks:

1. The composition of alkanes reflects the general formula:

a) C n H 2 n +2; b) C n H 2 n -2; c) C n H 2 n; d) C n H 2 n -6.

2. What reagents can alkanes interact with:

a) Br 2 (solution); b) Br 2 , t 0 ; in) H 2 SO 4 ; G) HNO 3 (dilute), t 0 ; d) KMnO 4 ; e) CON?

Answers: 1) reagents a, b, d, e; 2) reagents b, c, e;

3) reagents b, d; 4) reagents b, d, e, f.

1. Establish a correspondence between the type of reaction and the scheme (equation) of the reaction:

1. Specify the substance that is formed during the complete chlorination of methane:

a) trichloromethane; b) carbon tetrachloride; c) dichloromethane; d) tetrachloroethane.

1. Specify the most probable product of monobromination of 2,2,3-trimethylbutane:

a) 2-bromo-2,3,3-trimethylbutane; b) 1-bromo-2,2,3-trimethylbutane;

c) 1-bromo-2,3,3-trimethylbutane; d) 2-bromo-2,2,3-trimethylbutane.

Write an equation for the reaction.

Wurtz reaction – the action of metallic sodium on halogen derivatives of hydrocarbons. When two different halogen derivatives react, a mixture of hydrocarbons is formed, which can be separated by distillation.

CH 3 I + 2 Na + CH 3 I → C 2 H 6 + 2 NaI

@ Solve tasks:

1. Specify the name of the hydrocarbon that is formed when bromoethane is heated with sodium metal:

a) propane; b) butane; c) pentane; d) hexane; e) heptane.

Write an equation for the reaction.

1. What hydrocarbons are formed by the action of metallic sodium on a mixture:

a) iodomethane and 1-bromo-2-methylpropane; b) 2-bromopropane and 2-bromobutane?

Cycloalkanes

1. For small cycles (C 3 - C 4) are characteristic addition reactions hydrogen, halogens and hydrogen halides. The reactions are accompanied by the opening of the cycle.

2. For other cycles (from 5 and above) are characteristic substitution reactions.

Unsaturated hydrocarbons (unsaturated):

Alkenes (olefins, double bond unsaturated hydrocarbons, ethylene hydrocarbons): Structure: sp 2 hybridization, planar placement of orbitals (flat square). Reactions: addition (hydrogenation, halogenation, hydrohalogenation, polymerization), substitution (not typical), oxidation (combustion, KMnO 4), decomposition (without oxygen access).

@ Solve tasks:

1. What is the hybridization of carbon atoms in an alkene molecule:

a) 1 and 4 - sp 2, 2 and 3 - sp 3; b) 1 and 4 - sp 3, 2 and 3 - sp 2;

c) 1 and 4 - sp 3, 2 and 3 - sp; d) 1 and 4 - not hybridized, 2 and 3 - sp2.

2. Name the alkene:

1. Write reaction equations using the example of butene-1, name the products obtained.

4. In the transformation scheme below, ethylene is formed in the reaction:

a) 1 and 2; b) 1 and 3; c) 2 and 3;

d) ethylene is not formed in any reaction.

1. Which reaction goes against Markovnikov's rule:

a) CH 3 - CH \u003d CH 2 + HBr →; b) CH 3 - CH \u003d CH 2 + H 2 O →;;

c) CH 3 - CH \u003d CH - CH 2 + HCI →; d) CCI 3 - CH \u003d CH 2 + HCI →?

þ Dienes with conjugated bonds:hydration 1,3-butadiene - 2-butene is formed (1,4-addition):

þ hydrogenation 1,3-butadiene in the presence of a Ni-butane catalyst:

þ halogenation 1,3-butadiene - 1,4-addition (1,4 - dibromo-2-butene):

þ diene polymerization:

Polyena(unsaturated hydrocarbons with many double bonds) are hydrocarbons whose molecules contain at least three double bonds.

Obtaining dienes:

Ø action of an alcoholic solution of alkali:

Ø Lebedev method (divinyl synthesis):

Ø dehydration of glycols (alkanediols):

Alkynes (acetylenic hydrocarbons, hydrocarbons with one triple bond): Structure: sp hybridization, linear placement of orbitals. Reactions: addition (hydrogenation, halogenation, hydrohalogenation, polymerization), substitution (formation of salts), oxidation (combustion, KMnO 4), decomposition (without access to oxygen).	5-methylhexine-2 1-Pentyne 3-methylbutyne-1
	1. Which hydrocarbons correspond general formula C n H 2n-2: a) acetylene, diene; b) ethylene, diene; c) cycloalkanes, alkenes; d) acetylene, aromatic? 2. A triple bond is a combination of: a) three σ-bonds; b) one σ-bond and two π-bonds; c) two σ-bonds and one π-bond; d) three π-bonds. 3. Compose the formula of 3-methylpentine -3.
I. Addition reactions
v hydrogenation occurs through the stage of formation of alkenes:
v Addition of halogens happens worse than in alkenes: Alkynes decolorize bromine water (qualitative reaction).
v Addition of hydrogen halides:
Addition products to unsymmetrical alkynes are determined Markovnikov's rule:
v Accession of water (hydration)- reaction of M.G. Kucherov, 1881.
For acetylene homologues, the product of water addition is a ketone:
III. Salt formation ( acid properties) - substitution reactions
ð Interaction active metals : Acetylides are used for the synthesis of homologues.
ð Interaction of alkynes with ammonia solutions of silver oxide or copper(I) chloride:
Qualitative reaction to the final triple bond - the formation of a grayish-white precipitate of silver acetylenide or red-brown - copper (I) acetylenide:	HC ≡ CH + СuCI → СuC ≡ ССu ↓ + 2HCI Reaction does not occur
IV. Oxidation reactions
Ÿ mild oxidation– discoloration aqueous solution potassium permanganate ( a qualitative reaction to a multiple bond):	When acetylene interacts with a dilute solution of KMnO 4 (room temperature) - oxalic acid.

Electronic configuration an atom is a numerical representation of its electron orbitals. Electron orbitals are areas various shapes located around atomic nucleus, in which it is mathematically probable to find an electron. The electronic configuration helps to quickly and easily tell the reader how many electron orbitals an atom has, as well as to determine the number of electrons in each orbital. After reading this article, you will master the method of compiling electronic configurations.

Steps

Distribution of electrons using the periodic system of D. I. Mendeleev

Find atomic number your atom. Each atom has a certain number of electrons associated with it. Find the symbol for your atom in the periodic table. An atomic number is an integer positive number, starting from 1 (for hydrogen) and increasing by one for each subsequent atom. The atomic number is the number of protons in an atom, and therefore it is also the number of electrons in an atom with zero charge.

Determine the charge of an atom. Neutral atoms will have the same number of electrons as shown in the periodic table. However, charged atoms will have more or fewer electrons, depending on the magnitude of their charge. If you are working with a charged atom, add or subtract electrons as follows: add one electron for every negative charge and subtract one for every positive charge.

• For example, a sodium atom with a charge of -1 will have an extra electron in addition to its base atomic number of 11. In other words, an atom will have 12 electrons in total.
• If we are talking about a sodium atom with a charge of +1, one electron must be subtracted from the base atomic number 11. So the atom will have 10 electrons.

1. Memorize the basic list of orbitals. As the number of electrons increases in an atom, they fill the various sublevels of the electron shell of the atom according to a certain sequence. Each sublevel of the electron shell, when filled, contains even number electrons. There are the following sublevels:

   Understand the electronic configuration record. Electronic configurations are written down in order to clearly reflect the number of electrons in each orbital. Orbitals are written sequentially, with the number of atoms in each orbital written as a superscript to the right of the orbital name. The completed electronic configuration has the form of a sequence of sublevel designations and superscripts.

   • Here, for example, is the simplest electronic configuration: 1s 2 2s 2 2p 6 . This configuration shows that there are two electrons in the 1s sublevel, two electrons in the 2s sublevel, and six electrons in the 2p sublevel. 2 + 2 + 6 = 10 electrons in total. This is the electronic configuration of the neutral neon atom (neon atomic number is 10).

2. Remember the order of the orbitals. Keep in mind that electron orbitals are numbered in ascending order of electron shell number, but arranged in ascending energy order. For example, a filled 4s 2 orbital has less energy (or less mobility) than a partially filled or filled 3d 10, so the 4s orbital is written first. Once you know the order of the orbitals, you can easily fill them in according to the number of electrons in the atom. The order in which the orbitals are filled is as follows: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p.

   • The electronic configuration of an atom in which all orbitals are filled will have the following form: 10 7p 6
   • Note that the above notation, when all orbits are filled, is the electronic configuration of the element Uuo (ununoctium) 118, the highest numbered atom in the Periodic Table. Therefore, this electronic configuration contains all currently known electronic sublevels of a neutrally charged atom.

3. Fill in the orbitals according to the number of electrons in your atom. For example, if we want to write down the electronic configuration of a neutral calcium atom, we must start by looking up its atomic number in the periodic table. Its atomic number is 20, so we will write the configuration of an atom with 20 electrons according to the above order.

   • Fill in the orbitals in the above order until you reach the twentieth electron. The first 1s orbital will have two electrons, the 2s orbital will also have two, the 2p orbital will have six, the 3s orbital will have two, the 3p orbital will have 6, and the 4s orbital will have 2 (2 + 2 + 6 +2 +6 + 2 = 20 .) In other words, the electronic configuration of calcium has the form: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 .
   • Note that the orbitals are in ascending order of energy. For example, when you are ready to move to the 4th energy level, then first write down the 4s orbital, and then 3d. After the fourth energy level, you move on to the fifth, where the same order is repeated. This happens only after the third energy level.

4. Use the periodic table as a visual cue. You have probably already noticed that the shape of the periodic table corresponds to the order of electronic sublevels in electronic configurations. For example, atoms in the second column from the left always end in "s 2 ", while atoms on the right edge of the thin middle section always end in "d 10 ", and so on. Use the periodic table as a visual guide to writing configurations - as the order in which you add to the orbitals corresponds to your position in the table. See below:

   • In particular, the two leftmost columns contain atoms whose electronic configurations end in s orbitals, the right block of the table contains atoms whose configurations end in p orbitals, and at the bottom of the atoms end in f orbitals.
   • For example, when you write down the electronic configuration of chlorine, think like this: "This atom is located in the third row (or "period") of the periodic table. It is also located in the fifth group of the orbital block p of the periodic table. Therefore, its electronic configuration will end in. ..3p 5
   • Note that the elements in the d and f orbital regions of the table have energy levels that do not correspond to the period in which they are located. For example, the first row of a block of elements with d-orbitals corresponds to 3d orbitals, although it is located in the 4th period, and the first row of elements with f-orbitals corresponds to the 4f orbital, despite the fact that it is located in the 6th period.

5. Learn the abbreviations for writing long electronic configurations. The atoms on the right side of the periodic table are called noble gases. These elements are chemically very stable. To shorten the process of writing long electron configurations, simply write in square brackets the chemical symbol for the nearest noble gas with fewer electrons than your atom, and then continue to write the electronic configuration of subsequent orbital levels. See below:

   • To understand this concept, it will be helpful to write an example configuration. Let's write the configuration of zinc (atomic number 30) using the noble gas abbreviation. The complete zinc configuration looks like this: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 . However, we see that 1s 2 2s 2 2p 6 3s 2 3p 6 is the electronic configuration of argon, a noble gas. Simply replace the electronic configuration part of zinc with the chemical symbol for argon in square brackets (.)
   • So, the electronic configuration of zinc, written in abbreviated form, is: 4s 2 3d 10 .
   • Note that if you are writing the electronic configuration of a noble gas, say argon, you cannot write! One must use the abbreviation of the noble gas in front of this element; for argon it will be neon ().

   Using ADOMAH Periodic Table

   1. Master the ADOMAH periodic table. This method of recording the electronic configuration does not require memorization, however, it requires a redesigned periodic table, since in the traditional periodic table, starting from the fourth period, the period number does not correspond electron shell. Find the ADOMAH periodic table, a special type of periodic table designed by scientist Valery Zimmerman. It is easy to find with a short internet search.

      • In the ADOMAH periodic table, the horizontal rows represent groups of elements such as halogens, noble gases, alkali metals, alkaline earth metals etc. Vertical columns correspond to electronic levels, and the so-called "cascades" (diagonal lines connecting blocks s,p,d and f) correspond to periods.
      • Helium is moved to hydrogen, since both of these elements are characterized by a 1s orbital. The period blocks (s,p,d and f) are shown on the right side and the level numbers are given at the bottom. Elements are represented in boxes numbered from 1 to 120. These numbers are the usual atomic numbers that represent total electrons in a neutral atom.

   2. Find your atom in the ADOMAH table. To write down the electronic configuration of an element, find its symbol in the ADOMAH periodic table and cross out all elements with a higher atomic number. For example, if you need to write down the electronic configuration of erbium (68), cross out all the elements from 69 to 120.

      • Pay attention to the numbers from 1 to 8 at the base of the table. These are the electronic level numbers, or column numbers. Ignore columns that contain only crossed out items. For erbium, columns with numbers 1,2,3,4,5 and 6 remain.

   3. Count the orbital sublevels up to your element. Looking at the block symbols shown to the right of the table (s, p, d, and f) and the column numbers shown at the bottom, ignore the diagonal lines between the blocks and break the columns into block-columns, listing them in order from bottom to top. And again, ignore the blocks in which all the elements are crossed out. Write the column blocks starting from the column number followed by the block symbol, thus: 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 6s (for erbium).

      • Please note: The above electronic configuration Er is written in ascending order of the electronic sublevel number. It can also be written in the order in which the orbitals are filled. To do this, follow the cascades from bottom to top, not columns, when you write column blocks: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 12 .

   4. Count the electrons for each electronic sublevel. Count the elements in each column block that have not been crossed out by attaching one electron from each element, and write their number next to the block symbol for each column block as follows: 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 6 4d 10 4f 12 5s 2 5p 6 6s 2 . In our example, this is the electronic configuration of erbium.

   5. Be aware of incorrect electronic configurations. There are eighteen typical exceptions related to the electronic configurations of atoms in the lowest energy state, also called the ground energy state. They do not obey the general rule only in the last two or three positions occupied by electrons. In this case, the actual electronic configuration assumes that the electrons are in a state of lower energy compared to the standard configuration of the atom. Exception atoms include:

      • Cr(..., 3d5, 4s1); Cu(..., 3d10, 4s1); Nb(..., 4d4, 5s1); Mo(..., 4d5, 5s1); Ru(..., 4d7, 5s1); Rh(..., 4d8, 5s1); Pd(..., 4d10, 5s0); Ag(..., 4d10, 5s1); La(..., 5d1, 6s2); Ce(..., 4f1, 5d1, 6s2); Gd(..., 4f7, 5d1, 6s2); Au(..., 5d10, 6s1); AC(..., 6d1, 7s2); Th(..., 6d2, 7s2); Pa(..., 5f2, 6d1, 7s2); U(..., 5f3, 6d1, 7s2); Np(..., 5f4, 6d1, 7s2) and cm(..., 5f7, 6d1, 7s2).
   • To find the atomic number of an atom when it is written in electronic form, simply add up all the numbers that follow the letters (s, p, d, and f). This only works for neutral atoms, if you are dealing with an ion, then nothing will work - you will have to add or subtract the number of extra or lost electrons.
   • The number following the letter is a superscript, do not make a mistake in the control.
   • The "stability of a half-filled" sublevel does not exist. This is a simplification. Any stability that pertains to "half-full" sublevels is due to the fact that each orbital is occupied by one electron, so repulsion between electrons is minimized.
   • Each atom tends to a stable state, and the most stable configurations have filled sublevels s and p (s2 and p6). Noble gases have this configuration, so they rarely react and are located on the right in the periodic table. Therefore, if a configuration ends in 3p 4 , then it needs two electrons to reach a stable state (it takes more energy to lose six, including s-level electrons, so four is easier to lose). And if the configuration ends in 4d 3 , then it needs to lose three electrons to reach a stable state. In addition, half-filled sublevels (s1, p3, d5..) are more stable than, for example, p4 or p2; however, s2 and p6 will be even more stable.
   • When you're dealing with an ion, that means the number of protons is not the same as the number of electrons. The charge of the atom in this case will be shown at the top right (usually) of chemical symbol. Therefore, an antimony atom with a charge of +2 has the electronic configuration 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 1 . Note that 5p 3 has changed to 5p 1 . Be careful when the configuration of a neutral atom ends at sublevels other than s and p. When you take electrons, you can only take them from valence orbitals (s and p orbitals). Therefore, if the configuration ends with 4s 2 3d 7 and the atom gets +2 charge, then the configuration will end with 4s 0 3d 7 . Please note that 3d 7 not changes, instead electrons of the s-orbital are lost.
   • There are conditions when an electron is forced to "move to a higher energy level." When a sublevel lacks one electron to be half or full, take one electron from the nearest s or p sublevel and move it to the sublevel that needs an electron.
   • There are two options for writing an electronic configuration. They can be written in ascending order of the numbers of energy levels or in the order in which the electron orbitals are filled, as was shown above for erbium.
   • You can also write the electronic configuration of an element by writing only the valence configuration, which is the last s and p sublevel. Thus, the valence configuration of antimony will be 5s 2 5p 3 .
   • Ions are not the same. It's much more difficult with them. Skip two levels and follow the same pattern depending on where you started and how high the number of electrons is.