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 end up without agrochemicals? Will astrochemistry reveal the secret of life? Why is biochemistry needed? What's in galurgy from chemistry? Is geochemistry really the basis of raw materials “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 forests? Timber chemistry. Is life possible inside a magnet? Magnetochemistry. What is the relationship between medicinal chemistry and pathochemistry? What is different from chemistry in metallurgy? Why do we need mechanochemistry? Where do we encounter microwave chemistry? Nanochemistry – the size limit of chemistry? Who is leading us? Neurochemistry. Inorganic chemistry: old or new science? Sell oil or its refined products? Petrochemistry. You, me, he, she - together... organic chemistry? Perhaps we will someday synthesize the soul? Organic synthesis. Is it possible long life free particle in non-free matter? Physical organic chemistry. What is “pegniochemistry”? What does a disciple of Christ have in common with petrochemistry? Will we go back to the Stone Age? Peturgy. Will we go back to the Stone Age? Peturgy. How often do we use chemicals in the kitchen? Food chemistry. Plasma chemistry for people or for God? Applied chemistry for war or peace? What color is the electron? Radiation chemistry. Who discovered the phenomenon of radioactivity? How dangerous is radioactivity? Does languid energy exist? Radiochemistry. What is stereochemistry? What is better: a flood or a methane catastrophe? Supramolecular chemistry. What did D.I. talk about? Mendeleev in his doctoral dissertation? Thermochemistry. Technical chemistry – is the separation justified? Is topochemistry surface chemistry? Maybe we shouldn't burn coal? Coal chemistry. What is our treatment? Pharmacochemistry. Is femtochemistry something new? Is a blow to the head a crime or... physical chemistry? Who were the first phytochemists? Where does oxygen come from on Earth and what is the nature of vision? Photochemistry. How does high energy chemistry differ 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 bogeyman of the average person? Chemical Technology. What is the role of chemistry in wars? Chemical weapons. What are shopping bags, tires and agents of heredity 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 the chemistry of organoelement compounds? Electrochemistry, why do we need it? What pushes the boundaries of the Periodic Table? Nuclear chemistry. How to get into chemistry without a university? Which chemical element named after Russia? On the names 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 arbitrary. Item physical chemistry on the contrary: a chemical result of physical influence (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. Semyonov conducted in-depth research chain reactions. They are a series of self-initiating steps in a chemical reaction that, once started, continue 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 is therefore 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 react with another molecule, and the reaction continues until something prevents the free radicals from forming similar ones, 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 sites, but also multiply, creating new chains and speeding up the reaction. The actual progress of the reaction depends on a number of external limitations, such as the size of the vessel in which it occurs. If the number of free radicals increases rapidly, the reaction can lead to an explosion. In 1926 two students N.N. Semenov first observed this phenomenon while studying the oxidation of phosphorus vapor by water vapor. This reaction did not proceed as it should have, according to the laws of chemical kinetics of that 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 carried out his research in England independently, and after this period it became obvious that Semenov 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 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 paths of progress // Advances in chemistry. - 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 mentions of flammable liquids are found in the Bible.
According to the Old Testament, during the migration to India, the ancient Jews hid a sacred sacrificial fire in a well, causing the water to become thick and blazing with a bright flame. According to legend, it was black gold, with which Noah coated his ark, helped the ship withstand the uncontrollable flow of the Flood. The construction of the Tower of Babel was not without oil. Natural asphalt, obtained through the process of long-term weathering of a flammable substance, replaced the binding solution.
The healing power of oil
Historians claim that black gold was first mined 5-6 years BC. e. The most ancient 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. Written sources from Ancient Egypt say that earthen oil was used in medicine and in the embalming of mummies. Oil “baths” helped to cure joint pain, and bitumen ointments were prescribed for abscesses and skin diseases.
Let there be light!
There is evidence that Prometheus’s fire was also half composed of oil. The peoples living on the southern shore of the Caspian Sea have long used flammable substances 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 produce kerosene from it, which was used to fill lamps.
First oil well
At first, 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 reliable lubricants began to increase. For this reason, the date 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 River. At that time there were no cars yet, so “rock 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 global fuel and energy balance. It is impossible to imagine the activities of any industry without petroleum products. The significance of these natural resources greatly exceeds the value of gold of the highest standard.
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