I. ... AND IN GENERAL II. ABOUT SCIENCE III. ABOUT CHEMISTRY Is chemistry bad? Is medicine the mother of chemistry? A world without analytical chemistry. Apocalypse? How many crimes will not be solved without forensic chemistry? Where will we go without agrochemistry? Will astrochemistry reveal the secret of life? Why do we need biochemistry? What's in halurgy from chemistry? Is geochemistry the basis of raw materials "drug addiction"? Will hydrochemistry give us new "gold"? Why are the tissues of ... a person stained? Histochemistry and cytochemistry. Cancer, AIDS, flu... What science is really against? Immunochemistry Is it possible to calculate chemistry? quantum chemistry. How does jelly look like a person? colloidal chemistry. When does Catholicism recognize divorce? About cosmetic chemistry. Why do earthlings need cosmochemistry? Is the modern information field possible without crystal chemistry? How does Santa Claus help chemists and doctors? Cryochemistry and cryotherapy. Laser chemistry - what is it eaten with? Is it possible to fight without a forest? Forest chemistry. Is life possible inside a magnet? Magnetochemistry. What is the relationship between medicinal chemistry and pathochemistry? What in metallurgy from chemistry? Why do we need mechanochemistry? Where do we encounter microwave chemistry? Nanochemistry - the dimensional limit of chemistry? Who is leading us? Neurochemistry. Inorganic chemistry: old or new science? Sell oil or products of its processing? Petrochemistry. You, me, he, she - together ... organic chemistry? Perhaps we will synthesize the soul someday? organic synthesis. Is it possible long life free particle in non-free matter? Physical organic chemistry. What is "pegnochemistry"? What is common between a disciple of Christ and petrochemistry? Will we return to the stone age? Petrurgia. Will we return to the stone age? Petrurgia. How often do we chemise in the kitchen? Food chemistry. Plasma chemistry for people or for God? Applied chemistry for war or peace? What color is the electronic? Radiation chemistry. Who discovered the phenomenon of radioactivity? How dangerous is radioactivity? Does dark energy exist? Radiochemistry. What is stereochemistry? Which is better a flood or a methane catastrophe? supramolecular chemistry. What D.I. Mendeleev in his doctoral thesis? Thermochemistry. Technical chemistry - is isolation justified? Topochemistry is surface chemistry? Maybe you shouldn't burn coal? Coal chemistry. What are we treating? Pharmacochemistry. Femtochemistry - is it something new? Is a blow to the head a criminal act or ... physical chemistry? Who were the first phytochemists? Where does oxygen come from on Earth and what is the nature of vision? Photochemistry. How is high energy chemistry different from conventional chemistry? Is it possible to live without acceleration? Chemical kinetics and catalysis. How is chemical physics different from physical chemistry? What is the scarecrow of the layman? Chemical Technology. What is the role of chemistry in wars? Chemical weapons. What are shopping bags, tires, and heredity agents made of? Chemistry of macromolecular compounds. Is it possible to synthesize tea? Chemistry of natural compounds. Why do we need silicate chemistry? How does solid state chemistry answer the question: Is hetero-normal? What is organoelement chemistry? Electrochemistry, why do we need it? What pushes the boundaries of the Periodic Table? Nuclear chemistry. How to get to "chemistry" without a university? Which chemical element named after Russia? On the name of chemical elements.
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How is chemical physics different from physical chemistry?
Chemical physics studies the electronic structure of molecules and solids, molecular spectra, elementary acts of chemical reactions, combustion and explosion processes, that is physical aspects chemical phenomena. The term was introduced by the German chemist A. Eiken in 1930.
Formed in the 1920s. in connection with the development of quantum mechanics and the use of its concepts in chemistry. The boundary between chemical physics and physical chemistry is conditional. Subject physical chemistry on the contrary: the chemical result of a physical impact (for example, the death of a person as a result of hitting him on the head with a brick). One of the achievements of chemical physics should be considered the theory branched chain reactions.
Founder of the Institute of Chemical Physics of the Russian Academy of Sciences N.N. Semenov conducted in-depth research chain reactions. They are a series of self-initiating steps in a chemical reaction which, once started, continues until the last step is completed. Despite the fact that the German chemist M. Bodenstein first suggested the possibility of such reactions back in 1913, the theory explaining the stages chain reaction and showing its speed, did not exist. The key to the chain reaction is the initial stage of formation free radical- an atom or group of atoms that has an unpaired electron and, as a result, is extremely chemically active. Once formed, it interacts with the molecule in such a way that a new free radical is formed as one of the reaction products. The newly formed free radical can then interact with another molecule, and the reaction continues until something stops the free radicals from forming their own kind, i.e. until the circuit breaks.
A particularly important chain reaction is the branched chain reaction, discovered in 1923 by physicists G.A. Kramers and I.A. Christiansen. In this reaction, free radicals not only create active centers, but also multiply, creating new chains and speeding up the reaction. The actual course of the reaction depends on a number of external constraints, such as the size of the vessel in which it occurs. If the number of free radicals grows rapidly, then the reaction can lead to an explosion. In 1926 two students N.N. Semenov observed this phenomenon for the first time, studying the oxidation of phosphorus vapor with water vapor. This reaction did not proceed as it should have proceeded according to the laws of chemical kinetics of the time. Semenov saw the reason for this discrepancy in the fact that they were dealing with the result of a branched chain reaction. But such an explanation was rejected by M. Bodenstein, at that time a recognized authority on chemical kinetics. N.N. continued intensive study of this phenomenon for another two years. Semenov and S.N. Hinshelwood, who conducted his research in England independently, and after this period it became obvious that Semyonov was right.
N.N. Semenov published a monograph (Chain reactions. L., ONTI., 1934), in which he proved that many chemical reactions, including the polymerization reaction, are carried out using the mechanism of a chain or branched chain reaction. Later it was found that the fission reaction of uranium-235 nuclei by neutrons also has the character of a branched chain reaction.
In 1956, Semenov, together with Hinshelwood, was awarded the Nobel Prize in Chemistry "for research in the field of the mechanism of chemical reactions." In the Nobel lecture, Semenov stated: “The theory of a chain reaction opens up the possibility of coming closer to solving the main problem of theoretical chemistry - the relationship between the reactivity and structure of the particles that enter into the reaction ... It is hardly possible to enrich chemical technology or even achieve a decisive success in biology without this knowledge…”.
The Institute of Chemical Physics of the Russian Academy of Sciences (Moscow), the Institute of Problems of Chemical Physics of the Russian Academy of Sciences (Chernogolovka) work. There is a journal "Chemical Physics". You can read: Buchachenko A.L. Modern chemical physics: Goals and ways of progress // Uspekhi khimii. - 1987. - T. 56. - No. 11.
Oil is one of the main wealth of the country in which it is produced. The history of the discovery of this amazing creation of nature is complex and controversial, like earth oil itself. The first mention of a flammable liquid is found in the Bible.
According to the Old Testament, during the resettlement to India, the ancient Jews hid the sacred sacrificial fire in the well, because of which the water became thick and blazing with a bright flame. According to legend it is black gold, with which Noah smeared his ark, helped the ship withstand the unrestrained stream of the Flood. Not without oil and the construction of the Tower of Babel. Natural asphalt, obtained in the process of long-term weathering of a combustible substance, replaced the binding solution.
The healing power of oil
Historians claim that for the first time black gold began to be mined as early as 5-6 years BC. e. The oldest deposits include the Middle East, the banks of the Euphrates, the Chinese province of Sichuan, the Dead Sea region, as well as the Kerch and Tasman Peninsulas. In the written sources of Ancient Egypt, it is said that earthen oil was used in medicine and in embalming mummies. Oil "baths" helped to cure joint pain, and bituminous ointments were prescribed for abscesses and skin diseases.
Let there be light!
There is evidence that the fire of Prometheus also consisted of half oil. The peoples living on the southern coast of the Caspian Sea have long used a combustible substance as a source of light for their homes. In the Middle Ages, oil helped light the streets in the cities of southern Italy and the Middle East. In the 19th century, they learned to get kerosene from it, which was filled with lamps.
First oil well
Initially, oil was extracted in small quantities from shallow wells. In the second half of the 19th century, with the advent of steam engines and the intensive development of industry, the need for light sources and a reliable lubricant began to increase. For this reason, the date of August 28, 1859 is known to the world as the beginning of oil production from the first well drilled by American Colonel Edwin L. Drake at a depth of 22 m.
The oil industry originated in the United States in Pennsylvania near the Oil Creek. At that time, there were no cars yet, so "stone oil" was actively used in pharmaceuticals. At that time, oil already had an impressive price of $40 per barrel. Today, earth oil and natural gas help maintain the world's fuel and energy balance. Without petroleum products, it is impossible to imagine the activity of any industry. The significance of these natural resources in many ways exceeds the value of gold of the highest standard.
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