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7. Astronomy Cosmology Cosmology
Astrophysics Astrophysics
5. Тexts on chemistry in english for high school listening Atoms, Molecules and Ions

Nuclear physic

Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions. The most commonly known application of nuclear physics is nuclear power generation, but the research has led to applications in many fields, including nuclear medicine and magnetic resonance imaging, nuclear weapons, ion implantation in materials engineering, and radiocarbon dating ingeology and archaeology.
The field of particle physics evolved out of nuclear physics and is typically taught in close association with nuclear physics.
The history of nuclear physics as a discipline distinct from atomic physics

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starts with the discovery of radioactivity by Henri Becquerel in 1896,^[1] while investigating phosphorescence in uranium salts.^[2] The discovery of the electron by J. J. Thomson^[3] a year later was an indication that the atom had internal structure. At the beginning of the 20th century the accepted model of the atom was J. J. Thomson's "plum pudding" model in which the atom was a positively charged ball with smaller negatively charged electrons embedded inside it.
In the years that followed, radioactivity was extensively investigated, notably by the husband and wife team of Pierre Curie and Marie Curie and by Ernest Rutherford and his collaborators. By the turn of the century physicists had also discovered three types of radiation emanating from atoms, which they named alpha, beta, and gamma radiation. Experiments by Otto Hahn in 1911 and by James Chadwick in 1914 discovered that the beta decay spectrum was continuous rather than discrete. That is, electrons were ejected from the atom with a continuous range of energies, rather than the discrete amounts of energy that were observed in gamma and alpha decays. This was a problem for nuclear physics at the time, because it seemed to indicate that energy was not conserved in these decays.
The 1903 Nobel Prize in Physics was awarded jointly to Becquerel for his discovery and to Pierre Curie and Marie Curie for their subsequent research into radioactivity. Rutherford was awarded the Nobel Prize in Chemistry in 1908 for his "investigations into the disintegration of the elements and the chemistry of radioactive substances".
In 1905 Albert Einstein formulated the idea of mass–energy equivalence. While the work on radioactivity by Becquerel and Marie Curie predates this, an explanation of the source of the energy of radioactivity would have to wait for the discovery that the nucleus itself was composed of smaller constituents, the nucleons.
7. Astronomy
Cosmology

Cosmology (from the Greek κόσμος, kosmos "world" and -λογία, -logia "study of"), is the study of the origin, evolution, and eventual fate of the universe. Physical cosmology is the scholarly and scientific study of the origin, evolution, large-scale structures and dynamics, and ultimate fate of the universe, as well as the scientific laws that govern these realities.^[1]
The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia,^[2] and in 1731 taken up in Latin byGerman philosopher Christian Wolff, in Cosmologia Generalis.^[3]
Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions ofcreation and eschatology.
Physical cosmology is studied by scientists, such as astronomers and physicists, as well as philosophers, such asmetaphysicians, philosophers of physics, and philosophers of space and time. Because of this shared scope with philosophy,theories in physical cosmology may include both scientific and non-scientific propositions, and may depend upon assumptions that can not be tested.

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Cosmology differs from astronomy in that the former is concerned with the Universe as a whole while the latter deals with individual celestial objects. Modern physical cosmology is dominated by the Big Bang theory, which attempts to bring together observational astronomy and particle physics;^[4] more specifically, a standard parameterization of the Big Bang with dark matter and dark energy, known as the Lambda-CDM model.
Theoretical astrophysicist David N. Spergel has described cosmology as a
"historical science" because "when we look out in space, we look back in time" due to the finite nature of the speed of light.^[5]
Physics and astrophysics have played a central role in shaping the understanding of the universe through scientific observation and experiment. Physical cosmology was shaped through both mathematics and observation in an analysis of the whole universe. The universe is generally understood to have begun with the Big Bang, followed almost instantaneously by cosmic inflation; an expansion of space from which the universe is thought to have emerged 13.799 ± 0.021 billion years ago.^[6] Cosmogony studies the origin of the Universe, and cosmography maps the features of the Universe.
In Diderot's Encyclopédie, cosmology is broken down into uranology (the science of the heavens), aerology (the science of the air), geology (the science of the continents), and hydrology (the science of waters).^[7]
Metaphysical cosmology has also been described as the placing of man in the universe in relationship to all other entities. This is exemplified by Marcus Aurelius's observation that a man's place in that relationship: "He who does not know what the world is does not know where he is, and he who does not know for what purpose the world exists, does not know who he is, nor what the world is."^[8]
Astrophysics

Astrophysics is the branch of astronomy that employs the principles of physics
and chemistry "to ascertain the nature of theheavenly bodies, rather than their positions or motions in space."^[1][2] Among the objects studied are the Sun, other stars,
galaxies,extrasolar planets, the interstellar medium and the cosmic microwave background.^[3][4] Their emissions are examined across all parts of the electromagnetic
spectrum, and the properties examined include luminosity, density, temperature, and chemical composition. Because astrophysics is a very broad subject, astrophysicists typically apply many disciplines of physics, including mechanics,electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics.
In practice, modern astronomical research often involves a substantial amount of work in the realms of theoretical and observational physics. Some areas of study for astrophysicists include their attempts to determine: the properties of dark matter, dark energy, andblack holes; whether or not time travel is possible, wormholes can form, or the multiverse exists; and the origin and ultimate fate of the universe.^[3] Topics also studied by theoretical astrophysicists include: Solar System formation and evolution; stellar dynamics andevolution; galaxy formation and evolution; magnetohydrodynamics; large-scale structure of matter in the universe; origin of

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cosmic rays; general relativity and physical cosmology, including string cosmology and astroparticle physics.
Astrophysics can be studied at the bachelors, masters, and Ph.D. levels in physics or astronomy departments at many universities.
Although astronomy is as ancient as recorded history itself, it was long separated from the study of terrestrial physics. In the Aristotelianworldview, bodies in the sky appeared to be unchanging spheres whose only motion was uniform motion in a circle, while the earthly world was the realm which underwent growth and decay and in which natural motion was in a straight line and ended when the moving object reached its goal. Consequently, it was held that the celestial region was made of a

fundamentally different kind of matter from that found in the terrestrial sphere; either Fire as maintained by Plato, or Aether as maintained by Aristotle.^[5][6] During the 17th century, natural philosophers such as Galileo,^[7] Descartes,^[8] and Newton^[9] began to

maintain that the celestial and terrestrial regions were made of similar kinds of material and were subject to the same natural laws.^[10] Their challenge was that the tools had not yet been invented with which to prove these assertions.^[11]
For much of the nineteenth century, astronomical research was focused on the

routine work of measuring the positions and computing the motions of astronomical objects.^[12][13] A new astronomy, soon to be called astrophysics, began to emerge

when William Hyde Wollaston andJoseph von Fraunhofer independently discovered
that, when decomposing the light from the Sun, a multitude of dark lines (regions where there was less or no light) were observed in the spectrum.^[14] By 1860 the
physicist, Gustav Kirchhoff, and the chemist, Robert Bunsen, had demonstrated that the dark lines in the solar spectrum corresponded to bright lines in the spectra of known gases, specific lines corresponding to unique chemical elements.^[15] Kirchhoff
deduced that the dark lines in the solar spectrum are caused by absorption bychemical elements in the Solar atmosphere.^[16] In this way it was proved that the chemical
elements found in the Sun and stars were also found on Earth.

Among those who extended the study of solar and stellar spectra was Norman Lockyer, who in 1868 detected bright, as well as dark, lines in solar spectra. Working with the chemist, Edward Frankland, to investigate the spectra of elements at various temperatures and pressures, he could not associate a yellow line in the solar spectrum

with any known elements. He thus claimed the line represented a new element, which was called helium, after the GreekHelios, the Sun personified.^[17][18]
In 1885, Edward C. Pickering undertook an ambitious program of stellar spectral classification at Harvard College Observatory, in which a team of woman computers, notablyWilliamina Fleming, Antonia Maury, and Annie Jump Cannon, classified the spectra recorded on photographic plates. By 1890, a catalog of over 10,000 stars had been prepared that grouped them into thirteen spectral types. Following Pickering's vision, by 1924 Cannon expanded the catalog to nine volumes

and over a quarter of a million stars, developing the Harvard Classification Scheme which was accepted for world-wide use in 1922.^[19]

In 1895, George Ellery Hale and James E. Keeler, along with a group of ten associate editors from Europe and the United States,^[20] established The Astrophysical Journal: An International Review of Spectroscopy and Astronomical Physics.^[21] It

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was intended that the journal would fill the gap between journals in astronomy and physics, providing a venue for publication of articles on astronomical applications of the spectroscope; on laboratory research closely allied to astronomical physics, including wavelength determinations of metallic and gaseous spectra and experiments on radiation and absorption; on theories of the Sun, Moon, planets, comets, meteors, and nebulae; and on instrumentation for telescopes and laboratories.^[20]
In 1925 Cecilia Helena Payne (later Cecilia Payne-Gaposchkin) wrote an influential doctoral dissertation at Radcliffe College, in which she applied ionization theory to stellar atmospheres to relate the spectral classes to the temperature of stars.^[22] Most significantly, she discovered that hydrogen and helium were the principal components of stars. This discovery was so unexpected that her dissertation readers convinced her to modify the conclusion before publication. However, later research confirmed her discovery.^[23]
By the end of the 20th century, further study of stellar and experimental spectra advanced, particularly as a result of the advent of quantum physics.^[24]

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5. Тexts on chemistry in english for high school listening
Atoms, Molecules and Ions
All matter, whether living or nonliving, is made of the same tiny building blocks, called atoms. An atom is the smallest basic unit of matter. All atoms have the same basic structure, composed of three smaller particles.

Protons: A proton is a positively charged particle in an atom’s nucleus. The nucleus is the dense center of an atom

. • Neutrons: A neutron has no electrical charge, has about the same mass as a proton, and is also found in an atom’s nucleus.

Electrons: An electron is a negatively charged particle found outside the nucleus. Electrons are much smaller than either protons or neutrons. Different types of atoms are called elements, which cannot be broken down by ordinary chemical means. Which element an atom is depends on the number of protons in the atom’s nucleus. For example, all hydrogen atoms have one proton, and all oxygen atoms have 16 protons. Only about 25 different elements are found in organisms. Atoms of different elements can link, or bond, together to form compounds. Atoms form bonds in two ways.

Ionic bonds: An ion is an atom that has gained or lost one or more electrons. Some atoms form positive ions, which happens when an atom loses electrons. Other atoms form negative ions, which happens when an atom gains electrons. An ionic bond forms through the electrical force between oppositely charged ions. [1]

Covalent bonds: A covalent bond forms when atoms share one or more pairs of electrons. A molecule is two or more atoms that are held together by covalent bonds.

2.1 Laws of Chemical Combination—The basic laws of chemical combination are the law of conservation of mass, the law of constant composition, and the law of multiple proportions. Each played an important role in Dalton’s development of the atomic theory.

2.2 John Dalton and the Atomic Theory of Matter—Dalton developed his atomic theory to account for the basic laws of chemical combination. The theory centered around the existence of indivisible small particles of matter called atoms and addressed the unique nature of chemical elements, the formation of chemical compounds from atoms of different elements, and the atomic nature of chemical reactions.

2.3 The Divisible Atom—Of the fundamental particles found in atoms, the three of most concern to chemists are protons, neutrons, and electrons. Protons and neutrons make up the nucleus, and their combined number is the mass number, A, of the atom. The number of protons is the atomic number, Z. Electrons are found outside the nucleus, and their number is also equal to the atomic number. The negative charge on an electron is equal in magnitude to the positive charge on a proton. All atoms of an element have the same atomic number, but they may have different numbers of neutrons and hence different mass numbers. Atoms containing the same

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number of protons (atomic number) but different numbers of neutrons (mass number) are isotopes of an element. Chemical symbols for isotopes are commonly written in the form

with Abeing the mass number and Z the atomic number of the element E.
2.4 Atomic Masses—The atomic mass of an element is a weighted average value calculated from the masses and relative abundances of its naturally occurring isotopes. Theatomic mass unit represents the standard unit of measure of atomic masses; it is exactly

of the mass of a carbon-12 atom.
2.5 The Periodic Table: Elements Organized—The periodic table is an arrangement of the elements by atomic number into rows and columns. This arrangement places elements having similar properties in the same vertical groups (families). This arrangement also allows for the classification of elements as metal, nonmetal, or metalloid.
2.6 Molecules and Molecular Compounds—A chemical formula, the generic term for the various notations used to represent compounds, indicates the relative numbers of atoms of each type in a compound. An empirical formula expresses the simplest atom ratio, and a molecular formula reflects the actual composition of a molecule.Structural formulas describe the arrangement of atoms within molecules. Molecular models are also used to represent the structure and shape of molecules. For example, for acetic acid:

A molecular compound consists of molecules. In a binary molecular compound, the molecules are made up of atoms of two elements. In naming these compounds, the numbers of atoms in the molecules are denoted by prefixes; the names also feature -ide endings.

Examples: NI₃ = nitrogen triiodide S₂F₄ = disulfur tetrafluoride

2.7 Ions and Ionic Compounds—Ions are formed by the loss or gain of electrons by single atoms or groups of atoms. Positive ions are cations, and negative ions areanions. An ionic compound is made up of cations and anions held together by electrostatic attractions. Chemical formulas of ionic compounds are based on an electrically neutral combination of cations and anions called a formula unit, such as NaCl.

The names of some monatomic cations include roman numerals to designate the charge on the ion. The names of monatomic anions are those of the nonmetallic elements, modified to an -ide ending. Polyatomic ions contain more than one atom. For polyatomic anions, the prefixes hypo- and per- and the endings -ite and -ate are commonly used. A hydrate is an ionic compound that includes a fixed number of water molecules associated with the formula unit.
Examples:

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2.8 Acids, Bases, and Salts—According to the Arrhenius theory, an acid produces H⁺ in water and a base produces OH^-. A neutralization reaction between an acid and a base forms water and an ionic compound called a salt. Binary acids have hydrogen and a nonmetal as their constituent elements. Their names feature the prefix hydro- and the ending -ic attached to the stem of the name of the nonmetal. Ternary oxoacids have oxygen as an additional constituent element, and their names use prefixes (hypo- andper-) and endings (-ous and -ic) to indicate the number of O atoms per molecule.

Examples:

2.9 Organic Compounds—Organic compounds are based on the element carbon. Hydrocarbons contain only hydrogen and carbon. Alkanes have carbon atoms joined together by single bonds into chains or rings, with hydrogen atoms attached to the carbon atoms. Alkanes with four or more carbon atoms can exist as isomers, which are molecules that have the same molecular formula but different structures and properties.

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