Abundance of the chemical elements

The abundance of a chemical element measures how common the element is, or how much of the element there is. Abundance of the chemical elements - Abundance of elements in the Universe. Hydrogen is the most abundant element in the known Universe; helium is second. However, after this, the rank of abundance does not continue to correspond to the atomic number; oxygen has abundance rank 3, but atomic number 8. All others are orders of magnitude less common. Both helium-3 and helium-4 were produced in th ...

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• Abundance of the chemical elements - Abundance of elements in the Solar System
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• Abundance of the chemical elements - Ocean
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Scientists believe that the Earth formed from the same cloud of matter that formed the Sun. Abundance of the chemical elements - Abundance of elements in Earth's crust. The graphic below illustrates the relative abundance of the chemical elements in Earth's upper continental crust. Many of the elements shown in the graphic are classified into (partially overlapping) categories: rock-forming elements (major elements in green field and minor elements in light green field); ...

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Abundance of the chemical elements, Abundance of the chemical elements - Abundance of elements in the Universe, Abundance of the chemical elements - Abundance of elements in the Solar System, Abundance of the chemical elements - Abundance of elements in Earth, Abundance of the chemical elements - Abundance of elements in Earth's crust, Abundance of the chemical elements - Ocean, Abundance of the chemical elements - Atmosphere, Abundance of the chemical elements - Organisms, Abundance of the chemical elements - Human body

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A chemical element, often called simply element, is a chemical substance that cannot be divided or changed into other chemical substances by any ordinary chemical technique. The smallest unit of this kind of chemical substances is an atom. An element is a class of substances that contain the same number of protons in all its atoms. Chemical element - Chemistry terminology. Earlier an element or pure element was defined as a substance which "cannot be further broken down ...

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A group, also known as a family, is a vertical column in the periodic table of the elements. There are 18 groups or families in the standard periodic table. Elements in a group have similar configurations of their valence shell electrons, which gives them similar properties. There are three systems of group numbers; one using Hindu-Arabic numerals (1, 2, ... 18), another using Roman numerals (I, II, ... VIII), and one using a combination of Roman numerals and Latin letters (IA, IIA, IB, ... VIIIA). The Roman numeral names are the orig ...

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Periodic table, Periodic table - Groups, Periodic table - Periodicity of chemical properties, Periodic table - Methods for displaying the periodic table, Periodic table - Standard periodic table, Periodic table - Other depictions, Periodic table - Periodic table structure reflects electron configuration, Periodic table - History, Periodic table - Further resources

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The naming of elements precedes the atomic theory of matter, although at the time it was not known which chemicals were elements and which compounds. When it was learned, existing names (e.g., gold, mercury, iron) were kept in most countries, and national differences emerged over the names of elements either for convenience, linguistic niceties, or nationalism. For example, the Germans use "Wasserstoff" for "hydrogen" and "Sauerstoff" for "oxygen," while some romance languages use "natrium" for "sodium" and "kalium" for "potassium," and the French prefer the o ...

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Chemical element, Chemical element - Chemistry terminology, Chemical element - Description, Chemical element - Nomenclature, Chemical element - Chemical symbols, Chemical element - Specific chemical elements, Chemical element - General chemical symbols, Chemical element - Nonelement symbols

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The original table was created without a knowledge of the inner structure of atoms: if one orders the elements by atomic mass, and then plots certain other properties against atomic mass, one sees an undulation or periodicity to these properties as a function of atomic mass. The first to recognize these regularities was the German chemist Johann Wolfgang Döbereiner who, in 1829, noticed a number of triads of similar elements: This was followed by the English chemist John Newlands, who noticed in 1865 that the elements o ...

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Periodic table, Periodic table - Groups, Periodic table - Periodicity of chemical properties, Periodic table - Methods for displaying the periodic table, Periodic table - Standard periodic table, Periodic table - Other depictions, Periodic table - Periodic table structure reflects electron configuration, Periodic table - History, Periodic table - Further resources

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The primary determinant of an element's chemical properties is its electron configuration, particularly the valence shell electrons. For instance, all atoms whose four valence electrons are found on the p shell will behave similarly, regardless of which energy level that last p shell is on. The shell in which the atom's outermost electrons reside determines the "block" to which it belongs. Th ...

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Periodic table, Periodic table - Groups, Periodic table - Periodicity of chemical properties, Periodic table - Methods for displaying the periodic table, Periodic table - Standard periodic table, Periodic table - Other depictions, Periodic table - Periodic table structure reflects electron configuration, Periodic table - History, Periodic table - Further resources

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The atomic number of an element, Z, is equal to the number of protons which defines the element. For example, all carbon atoms contain 6 protons in their nucleus, so for carbon Z=6. These atoms may have different amounts of neutrons, and are known as isotopes of the element. The atomic mass of an element, A, is measured in unified atomic mass units (u) is the average mass of all the atoms of the element in an environment of interest (usually the earth's crust and atmosphere). Since electrons are light, and neutrons are barely m ...

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Chemical element, Chemical element - Chemistry terminology, Chemical element - Description, Chemical element - Nomenclature, Chemical element - Chemical symbols, Chemical element - Specific chemical elements, Chemical element - General chemical symbols, Chemical element - Nonelement symbols

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Earlier an element or pure element was defined as a substance which "cannot be further broken down into another compound with different chemical properties" -- which should be taken to mean it consists of atoms of one element. However, due to allotropy, the isotope effect, and the confusion with the more useful term referring to the general class of atoms (irrespective of what compound it may be in), this usage is in disfavor amongst contemporary chemists, and sees restricted, mostly historical, use. This definition was motivat ...

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Chemical element, Chemical element - Chemistry terminology, Chemical element - Description, Chemical element - Nomenclature, Chemical element - Chemical symbols, Chemical element - Specific chemical elements, Chemical element - General chemical symbols, Chemical element - Nonelement symbols

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Chemical element - Specific chemical elements. Before chemistry became a science, alchemists had designed arcane symbols for both metals and common compounds. These were however used as abbreviations in diagrams or procedures; there was no concept of one atoms combining to form molecules. With his advances in the atomic theory of matter, John Dalton devised his own simpler symbols, based on circles, which were to be used to depict molecules. These were superceded by the current typographical system in which chemi ...

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Chemical element, Chemical element - Chemistry terminology, Chemical element - Description, Chemical element - Nomenclature, Chemical element - Chemical symbols, Chemical element - Specific chemical elements, Chemical element - General chemical symbols, Chemical element - Nonelement symbols

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Elements adjacent to one another within a group have similar physical properties, despite their significant differences in mass. Elements adjacent to one another within a period, or energy level, have similar mass but different properties. For example, very near to nitrogen (N) in the second period of the chart are carbon (C) and oxygen (O). Despite their similarities in mass (only a few atomic mass units), they have extremely different properties, as can be seen by looking at their allotropes: diatomic oxygen is a gas that supports burning, diatomic nitrogen is a gas that d ...

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Periodic table, Periodic table - Groups, Periodic table - Periodicity of chemical properties, Periodic table - Methods for displaying the periodic table, Periodic table - Standard periodic table, Periodic table - Other depictions, Periodic table - Periodic table structure reflects electron configuration, Periodic table - History, Periodic table - Further resources

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Periodic table - Standard periodic table. 1Actinides and lanthanides are collectively known as "Rare Earth Metals". 2Alkali metals, alkaline earth metals, transition metals, actinides, lanthanides, and poor metals are all collectively known as "Metals". 3Halogens and noble gases are also non-metals. State at standard temperature and pressure those with atomic number in red are gases those with ...

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Periodic table, Periodic table - Groups, Periodic table - Periodicity of chemical properties, Periodic table - Methods for displaying the periodic table, Periodic table - Standard periodic table, Periodic table - Other depictions, Periodic table - Periodic table structure reflects electron configuration, Periodic table - History, Periodic table - Further resources

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Hydrogen is the most abundant element in the known Universe; helium is second. However, after this, the rank of abundance does not continue to correspond to the atomic number; oxygen has abundance rank 3, but atomic number 8. All others are orders of magnitude less common. Both helium-3 and helium-4 were produced in the Big Bang. Additional helium is produced by the fusion of hydrogen inside stellar cores, via a process called the proton-proton chain. Hydrogen and helium are estimated to make up roughly 80% and 20% of all the m ...

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Abundance of the chemical elements, Abundance of the chemical elements - Abundance of elements in the Universe, Abundance of the chemical elements - Abundance of elements in the Solar System, Abundance of the chemical elements - Abundance of elements in Earth, Abundance of the chemical elements - Abundance of elements in Earth's crust, Abundance of the chemical elements - Ocean, Abundance of the chemical elements - Atmosphere, Abundance of the chemical elements - Organisms, Abundance of the chemical elements - Human body

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The Solar System was created from the remnants of previous stellar systems that went supernova, and is hence, relative to the rest of the universe, richer in heavier elements. Population I stars contain significant amounts of elements heavier than helium ("metals", in the terminology of astronomers). These heavy elements were produced by earlier generations of stars and spread by supernova explosions ...

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Abundance of the chemical elements, Abundance of the chemical elements - Abundance of elements in the Universe, Abundance of the chemical elements - Abundance of elements in the Solar System, Abundance of the chemical elements - Abundance of elements in Earth, Abundance of the chemical elements - Abundance of elements in Earth's crust, Abundance of the chemical elements - Ocean, Abundance of the chemical elements - Atmosphere, Abundance of the chemical elements - Organisms, Abundance of the chemical elements - Human body

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