document_title: Chemical element

question_text: who gave the first working definition of an element

question_tokens: who gave the first working definition of an element

text: Chemical element

text: Description

text: The lightest chemical elements are hydrogen and helium, both created by Big Bang nucleosynthesis during the first 20 minutes of the universe[5] in a ratio of around 3:1 by mass (or 12:1 by number of atoms),[6][7] along with tiny traces of the next two elements, lithium and beryllium. Almost all other elements found in nature were made by various natural methods of nucleosynthesis.[8] On Earth, small amounts of new atoms are naturally produced in nucleogenic reactions, or in cosmogenic processes, such as cosmic ray spallation. New atoms are also naturally produced on Earth as radiogenic daughter isotopes of ongoing radioactive decay processes such as alpha decay, beta decay, spontaneous fission, cluster decay, and other rarer modes of decay.

text: Of the 94 naturally occurring elements, those with atomic numbers 1 through 82 each have at least one stable isotope (except for technetium, element 43 and promethium, element 61, which have no stable isotopes). Isotopes considered stable are those for which no radioactive decay has yet been observed. Elements with atomic numbers 83 through 94 are unstable to the point that radioactive decay of all isotopes can be detected. Some of these elements, notably bismuth (atomic number 83), thorium (atomic number 90), and uranium (atomic number 92), have one or more isotopes with half-lives long enough to survive as remnants of the explosive stellar nucleosynthesis that produced the heavy metals before the formation of our Solar System. At over 1.9×1019 years, over a billion times longer than the current estimated age of the universe, bismuth-209 (atomic number 83) has the longest known alpha decay half-life of any naturally occurring element, and is almost always considered on par with the 80 stable elements.[9][10] The very heaviest elements (those beyond plutonium, element 94) undergo radioactive decay with half-lives so short that they are not found in nature and must be synthesized.

text: As of 2010, there are 118 known elements (in this context, "known" means observed well enough, even from just a few decay products, to have been differentiated from other elements).[11][12] Of these 118 elements, 94 occur naturally on Earth. Six of these occur in extreme trace quantities: technetium, atomic number 43; promethium, number 61; astatine, number 85; francium, number 87; neptunium, number 93; and plutonium, number 94. These 94 elements have been detected in the universe at large, in the spectra of stars and also supernovae, where short-lived radioactive elements are newly being made. The first 94 elements have been detected directly on Earth as primordial nuclides present from the formation of the solar system, or as naturally occurring fission or transmutation products of uranium and thorium.

text: The remaining 24 heavier elements, not found today either on Earth or in astronomical spectra, have been produced artificially: these are all radioactive, with very short half-lives; if any atoms of these elements were present at the formation of Earth, they are extremely likely, to the point of certainty, to have already decayed, and if present in novae, have been in quantities too small to have been noted. Technetium was the first purportedly non-naturally occurring element synthesized, in 1937, although trace amounts of technetium have since been found in nature (and also the element may have been discovered naturally in 1925).[13] This pattern of artificial production and later natural discovery has been repeated with several other radioactive naturally occurring rare elements.[14]

text: List of the elements are available by name, atomic number, density, melting point, boiling point and by symbol, as well as ionization energies of the elements. The nuclides of stable and radioactive elements are also available as a list of nuclides, sorted by length of half-life for those that are unstable. One of the most convenient, and certainly the most traditional presentation of the elements, is in the form of the periodic table, which groups together elements with similar chemical properties (and usually also similar electronic structures).

text: Atomic number

text: The atomic number of an element is equal to the number of protons in each atom, and defines the element.[15] For example, all carbon atoms contain 6 protons in their atomic nucleus; so the atomic number of carbon is 6.[16] Carbon atoms may have different numbers of neutrons; atoms of the same element having different numbers of neutrons are known as isotopes of the element.[17]

text: The number of protons in the atomic nucleus also determines its electric charge, which in turn determines the number of electrons of the atom in its non-ionized state. The electrons are placed into atomic orbitals that determine the atom's various chemical properties. The number of neutrons in a nucleus usually has very little effect on an element's chemical properties (except in the case of hydrogen and deuterium). Thus, all carbon isotopes have nearly identical chemical properties because they all have six protons and six electrons, even though carbon atoms may, for example, have 6 or 8 neutrons. That is why the atomic number, rather than mass number or atomic weight, is considered the identifying characteristic of a chemical element.

text: The symbol for atomic number is Z.

text: Isotopes

text: Isotopes are atoms of the same element (that is, with the same number of protons in their atomic nucleus), but having different numbers of neutrons. Thus, for example, there are three main isotopes of carbon. All carbon atoms have 6 protons in the nucleus, but they can have either 6, 7, or 8 neutrons. Since the mass numbers of these are 12, 13 and 14 respectively, the three isotopes of carbon are known as carbon-12, carbon-13, and carbon-14, often abbreviated to 12C, 13C, and 14C. Carbon in everyday life and in chemistry is a mixture of 12C (about 98.9%), 13C (about 1.1%) and about 1 atom per trillion of 14C.

text: Most (66 of 94) naturally occurring elements have more than one stable isotope. Except for the isotopes of hydrogen (which differ greatly from each other in relative mass—enough to cause chemical effects), the isotopes of a given element are chemically nearly indistinguishable.

text: All of the elements have some isotopes that are radioactive (radioisotopes), although not all of these radioisotopes occur naturally. The radioisotopes typically decay into other elements upon radiating an alpha or beta particle. If an element has isotopes that are not radioactive, these are termed "stable" isotopes. All of the known stable isotopes occur naturally (see primordial isotope). The many radioisotopes that are not found in nature have been characterized after being artificially made. Certain elements have no stable isotopes and are composed only of radioactive isotopes: specifically the elements without any stable isotopes are technetium (atomic number 43), promethium (atomic number 61), and all observed elements with atomic numbers greater than 82.

text: Of the 80 elements with at least one stable isotope, 26 have only one single stable isotope. The mean number of stable isotopes for the 80 stable elements is 3.1 stable isotopes per element. The largest number of stable isotopes that occur for a single element is 10 (for tin, element 50).

text: Isotopic mass and atomic mass

text: The mass number of an element, A, is the number of nucleons (protons and neutrons) in the atomic nucleus. Different isotopes of a given element are distinguished by their mass numbers, which are conventionally written as a superscript on the left hand side of the atomic symbol (e.g. 238U). The mass number is always a whole number and has units of "nucleons". For example, magnesium-24 (24 is the mass number) is an atom with 24 nucleons (12 protons and 12 neutrons).

text: Whereas the mass number simply counts the total number of neutrons and protons and is thus a natural (or whole) number, the atomic mass of a single atom is a real number giving the mass of a particular isotope (or "nuclide") of the element, expressed in atomic mass units (u). In general, the mass number of a given nuclide differs in value slightly from its atomic mass, since the mass of each proton and neutron is not exactly 1 u; since the electrons contribute a lesser share to the atomic mass as neutron number exceeds proton number; and (finally) because of the nuclear binding energy. For example, the atomic mass of chlorine-35 to five significant digits is 34.969 u and that of chlorine-37 is 36.966 u. However, the atomic mass in u of each isotope is quite close to its simple mass number (always within 1%). The only isotope whose atomic mass is exactly a natural number is 12C, which by definition has a mass of exactly 12, because u is defined as 1/12 of the mass of a free neutral carbon-12 atom in the ground state.

text: The standard atomic weight (commonly called "atomic weight") of an element is the average of the atomic masses of all the chemical element's isotopes as found in a particular environment, weighted by isotopic abundance, relative to the atomic mass unit (u). This number may be a fraction that is not close to a whole number. For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number as it is an average of about 76% chlorine-35 and 24% chlorine-37. Whenever a relative atomic mass value differs by more than 1% from a whole number, it is due to this averaging effect, as significant amounts of more than one isotope are naturally present in a sample of that element.

text: Chemically pure and isotopically pure

text: Chemists and nuclear scientists have different definitions of a pure element. In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the same atomic number, or number of protons. Nuclear scientists, however, define a pure element as one that consists of only one stable isotope.[18]

text: For example, a copper wire is 99.99% chemically pure if 99.99% of its atoms are copper, with 29 protons each. However it is not isotopically pure since ordinary copper consists of two stable isotopes, 69% 63Cu and 31% 65Cu, with different numbers of neutrons. However, a pure gold ingot would be both chemically and isotopically pure, since ordinary gold consists only of one isotope, 197Au.

text: Allotropes

text: Atoms of chemically pure elements may bond to each other chemically in more than one way, allowing the pure element to exist in multiple chemical structures (spatial arrangements of atoms), known as allotropes, which differ in their properties. For example, carbon can be found as diamond, which has a tetrahedral structure around each carbon atom; graphite, which has layers of carbon atoms with a hexagonal structure stacked on top of each other; graphene, which is a single layer of graphite that is very strong; fullerenes, which have nearly spherical shapes; and carbon nanotubes, which are tubes with a hexagonal structure (even these may differ from each other in electrical properties). The ability of an element to exist in one of many structural forms is known as 'allotropy'.

text: The standard state, also known as reference state, of an element is defined as its thermodynamically most stable state at a pressure of 1 bar and a given temperature (typically at 298.15 K). In thermochemistry, an element is defined to have an enthalpy of formation of zero in its standard state. For example, the reference state for carbon is graphite, because the structure of graphite is more stable than that of the other allotropes.

text: Properties

text: Several kinds of descriptive categorizations can be applied broadly to the elements, including consideration of their general physical and chemical properties, their states of matter under familiar conditions, their melting and boiling points, their densities, their crystal structures as solids, and their origins.

text: General properties

text: Several terms are commonly used to characterize the general physical and chemical properties of the chemical elements. A first distinction is between metals, which readily conduct electricity, nonmetals, which do not, and a small group, (the metalloids), having intermediate properties and often behaving as semiconductors.

text: A more refined classification is often shown in colored presentations of the periodic table. This system restricts the terms "metal" and "nonmetal" to only certain of the more broadly defined metals and nonmetals, adding additional terms for certain sets of the more broadly viewed metals and nonmetals. The version of this classification used in the periodic tables presented here includes: actinides, alkali metals, alkaline earth metals, halogens, lanthanides, transition metals, post-transition metals, metalloids, polyatomic nonmetals, diatomic nonmetals, and noble gases. In this system, the alkali metals, alkaline earth metals, and transition metals, as well as the lanthanides and the actinides, are special groups of the metals viewed in a broader sense. Similarly, the polyatomic nonmetals, diatomic nonmetals and the noble gases are nonmetals viewed in the broader sense. In some presentations, the halogens are not distinguished, with astatine identified as a metalloid and the others identified as nonmetals.

text: States of matter

text: Another commonly used basic distinction among the elements is their state of matter (phase), whether solid, liquid, or gas, at a selected standard temperature and pressure (STP). Most of the elements are solids at conventional temperatures and atmospheric pressure, while several are gases. Only bromine and mercury are liquids at 0 degrees Celsius (32 degrees Fahrenheit) and normal atmospheric pressure; caesium and gallium are solids at that temperature, but melt at 28.4 °C (83.2 °F) and 29.8 °C (85.6 °F), respectively.

text: Melting and boiling points

text: Melting and boiling points, typically expressed in degrees Celsius at a pressure of one atmosphere, are commonly used in characterizing the various elements. While known for most elements, either or both of these measurements is still undetermined for some of the radioactive elements available in only tiny quantities. Since helium remains a liquid even at absolute zero at atmospheric pressure, it has only a boiling point, and not a melting point, in conventional presentations.

text: Densities

text: The density at a selected standard temperature and pressure (STP) is frequently used in characterizing the elements. Density is often expressed in grams per cubic centimeter (g/cm3). Since several elements are gases at commonly encountered temperatures, their densities are usually stated for their gaseous forms; when liquefied or solidified, the gaseous elements have densities similar to those of the other elements.

text: When an element has allotropes with different densities, one representative allotrope is typically selected in summary presentations, while densities for each allotrope can be stated where more detail is provided. For example, the three familiar allotropes of carbon (amorphous carbon, graphite, and diamond) have densities of 1.8–2.1, 2.267, and 3.515 g/cm3, respectively.

text: Crystal structures

text: The elements studied to date as solid samples have eight kinds of crystal structures: cubic, body-centered cubic, face-centered cubic, hexagonal, monoclinic, orthorhombic, rhombohedral, and tetragonal. For some of the synthetically produced transuranic elements, available samples have been too small to determine crystal structures.

text: Occurrence and origin on Earth

text: Chemical elements may also be categorized by their origin on Earth, with the first 94 considered naturally occurring, while those with atomic numbers beyond 94 have only been produced artificially as the synthetic products of man-made nuclear reactions.

text: Of the 94 naturally occurring elements, 84 are considered primordial and either stable or weakly radioactive. The remaining 10 naturally occurring elements possess half lives too short for them to have been present at the beginning of the Solar System, and are therefore considered transient elements. (Plutonium is usually also considered a transient element because primordial plutonium has by now decayed to almost undetectable traces.) Of these 10 transient elements, 5 (polonium, radon, radium, actinium, and protactinium) are relatively common decay products of thorium, uranium, and plutonium. The remaining 6 transient elements (technetium, promethium, astatine, francium, neptunium, and plutonium) occur only rarely, as products of rare decay modes or nuclear reaction processes involving uranium or other heavy elements.

text: Elements with atomic numbers 1 through 40 are all stable, while those with atomic numbers 41 through 82 (except technetium and promethium) are metastable.[citation needed] The half-lives of these metastable "theoretical radionuclides" are so long (at least 100 million times longer than the estimated age of the universe) that their radioactive decay has yet to be detected by experiment. Elements with atomic numbers 83 through 94 are unstable to the point that their radioactive decay can be detected. Three of these elements, bismuth (element 83), thorium (element 90), and uranium (element 92) have one or more isotopes with half-lives long enough to survive as remnants of the explosive stellar nucleosynthesis that produced the heavy elements before the formation of our solar system. For example, at over 1.9×1019 years, over a billion times longer than the current estimated age of the universe, bismuth-209 has the longest known alpha decay half-life of any naturally occurring element.[9][10] The very heaviest 24 elements (those beyond plutonium, element 94) undergo radioactive decay with short half-lives and cannot be produced as daughters of longer-lived elements, and thus they do not occur in nature at all.

text: The periodic table

text:
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v
t
e

Periodic table

Group
1
2
3

4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

Alkali metals
Alkaline earth metals

Pnictogens
Chalcogens
Halogens
Noble gases

Period
1

Hydrogen1H

Helium2He

2
Lithium3Li
Beryllium4Be

Boron5B
Carbon6C
Nitrogen7N
Oxygen8O
Fluorine9F
Neon10Ne

3
Sodium11Na
Magnesium12Mg

Aluminium13Al
Silicon14Si
Phosphorus15P
Sulfur16S
Chlorine17Cl
Argon18Ar

4
Potassium19K
Calcium20Ca
Scandium21Sc

Titanium22Ti
Vanadium23V
Chromium24Cr
Manganese25Mn
Iron26Fe
Cobalt27Co
Nickel28Ni
Copper29Cu
Zinc30Zn
Gallium31Ga
Germanium32Ge
Arsenic33As
Selenium34Se
Bromine35Br
Krypton36Kr

5
Rubidium37Rb
Strontium38Sr
Yttrium39Y

Zirconium40Zr
Niobium41Nb
Molybdenum42Mo
Technetium43Tc
Ruthenium44Ru
Rhodium45Rh
Palladium46Pd
Silver47Ag
Cadmium48Cd
Indium49In
Tin50Sn
Antimony51Sb
Tellurium52Te
Iodine53I
Xenon54Xe

6
Caesium55Cs
Barium56Ba
Lanthanum57La

Hafnium72Hf
Tantalum73Ta
Tungsten74W
Rhenium75Re
Osmium76Os
Iridium77Ir
Platinum78Pt
Gold79Au
Mercury80Hg
Thallium81Tl
Lead82Pb
Bismuth83Bi
Polonium84Po
Astatine85At
Radon86Rn

7
Francium87Fr
Radium88Ra
Actinium89Ac

Rutherfordium104Rf
Dubnium105Db
Seaborgium106Sg
Bohrium107Bh
Hassium108Hs
Meitnerium109Mt
Darmstadtium110Ds
Roentgenium111Rg
Copernicium112Cn
Nihonium113Nh
Flerovium114Fl
Moscovium115Mc
Livermorium116Lv
Tennessine117Ts
Oganesson118Og

Cerium58Ce
Praseodymium59Pr
Neodymium60Nd
Promethium61Pm
Samarium62Sm
Europium63Eu
Gadolinium64Gd
Terbium65Tb
Dysprosium66Dy
Holmium67Ho
Erbium68Er
Thulium69Tm
Ytterbium70Yb
Lutetium71Lu

Thorium90Th
Protactinium91Pa
Uranium92U
Neptunium93Np
Plutonium94Pu
Americium95Am
Curium96Cm
Berkelium97Bk
Californium98Cf
Einsteinium99Es
Fermium100Fm
Mendelevium101Md
Nobelium102No
Lawrencium103Lr

black=solid
green=liquid
red=gas
gray=unknown
Color of the atomic number shows state of matter (at 0 °C and 1 atm)

Primordial

From decay

Synthetic
Border shows natural occurrence of the element

Background color shows subcategory in the metal–metalloid–nonmetal trend:

Metal
Metalloid
Nonmetal
Unknown
chemical
properties

Alkali metal
Alkaline earth metal
Lanthanide
Actinide
Transition metal
Post-transition metal
Polyatomic nonmetal
Diatomic nonmetal
Noble gas

text: The properties of the chemical elements are often summarized using the periodic table, which powerfully and elegantly organizes the elements by increasing atomic number into rows ("periods") in which the columns ("groups") share recurring ("periodic") physical and chemical properties. The current standard table contains 118 confirmed elements as of 10 April 2010.

text: Although earlier precursors to this presentation exist, its invention is generally credited to the Russian chemist Dmitri Mendeleev in 1869, who intended the table to illustrate recurring trends in the properties of the elements. The layout of the table has been refined and extended over time as new elements have been discovered and new theoretical models have been developed to explain chemical behavior.

text: Use of the periodic table is now ubiquitous within the academic discipline of chemistry, providing an extremely useful framework to classify, systematize and compare all the many different forms of chemical behavior. The table has also found wide application in physics, geology, biology, materials science, engineering, agriculture, medicine, nutrition, environmental health, and astronomy. Its principles are especially important in chemical engineering.

text: Nomenclature and symbols

text: The various chemical elements are formally identified by their unique atomic numbers, by their accepted names, and by their symbols.

text: Atomic numbers

text: The known elements have atomic numbers from 1 through 118, conventionally presented as Arabic numerals. Since the elements can be uniquely sequenced by atomic number, conventionally from lowest to highest (as in a periodic table), sets of elements are sometimes specified by such notation as "through", "beyond", or "from ... through", as in "through iron", "beyond uranium", or "from lanthanum through lutetium". The terms "light" and "heavy" are sometimes also used informally to indicate relative atomic numbers (not densities), as in "lighter than carbon" or "heavier than lead", although technically the weight or mass of atoms of an element (their atomic weights or atomic masses) do not always increase monotonically with their atomic numbers.

text: Element names

text: The naming of various substances now known as elements precedes the atomic theory of matter, as names were given locally by various cultures to various minerals, metals, compounds, alloys, mixtures, and other materials, although at the time it was not known which chemicals were elements and which compounds. As they were identified as elements, the existing names for anciently-known elements (e.g., gold, mercury, iron) were kept in most countries. National differences emerged over the names of elements either for convenience, linguistic niceties, or nationalism. For a few illustrative examples: German speakers use "Wasserstoff" (water substance) for "hydrogen", "Sauerstoff" (acid substance) for "oxygen" and "Stickstoff" (smothering substance) for "nitrogen", while English and some romance languages use "sodium" for "natrium" and "potassium" for "kalium", and the French, Italians, Greeks, Portuguese and Poles prefer "azote/azot/azoto" (from roots meaning "no life") for "nitrogen".

text: For purposes of international communication and trade, the official names of the chemical elements both ancient and more recently recognized are decided by the International Union of Pure and Applied Chemistry (IUPAC), which has decided on a sort of international English language, drawing on traditional English names even when an element's chemical symbol is based on a Latin or other traditional word, for example adopting "gold" rather than "aurum" as the name for the 79th element (Au). IUPAC prefers the British spellings "aluminium" and "caesium" over the U.S. spellings "aluminum" and "cesium", and the U.S. "sulfur" over the British "sulphur". However, elements that are practical to sell in bulk in many countries often still have locally used national names, and countries whose national language does not use the Latin alphabet are likely to use the IUPAC element names.

text: According to IUPAC, chemical elements are not proper nouns in English; consequently, the full name of an element is not routinely capitalized in English, even if derived from a proper noun, as in californium and einsteinium. Isotope names of chemical elements are also uncapitalized if written out, e.g., carbon-12 or uranium-235. Chemical element symbols (such as Cf for californium and Es for einsteinium), are always capitalized (see below).

text: In the second half of the twentieth century, physics laboratories became able to produce nuclei of chemical elements with half-lives too short for an appreciable amount of them to exist at any time. These are also named by IUPAC, which generally adopts the name chosen by the discoverer. This practice can lead to the controversial question of which research group actually discovered an element, a question that delayed the naming of elements with atomic number of 104 and higher for a considerable amount of time. (See element naming controversy).

text: Precursors of such controversies involved the nationalistic namings of elements in the late 19th century. For example, lutetium was named in reference to Paris, France. The Germans were reluctant to relinquish naming rights to the French, often calling it cassiopeium. Similarly, the British discoverer of niobium originally named it columbium, in reference to the New World. It was used extensively as such by American publications prior to the international standardization (in 1950).

text: Chemical symbols

text: Specific chemical elements

text: 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 atoms combining to form molecules. With his advances in the atomic theory of matter, John Dalton devised his own simpler symbols, based on circles, to depict molecules.

text: The current system of chemical notation was invented by Berzelius. In this typographical system, chemical symbols are not mere abbreviations—though each consists of letters of the Latin alphabet. They are intended as universal symbols for people of all languages and alphabets.

text: The first of these symbols were intended to be fully universal. Since Latin was the common language of science at that time, they were abbreviations based on the Latin names of metals. Cu comes from Cuprum, Fe comes from Ferrum, Ag from Argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin natrium. The same applies to "W" (wolfram) for tungsten, "Fe" (ferrum) for iron, "Hg" (hydrargyrum) for mercury, "Sn" (stannum) for tin, "K" (kalium) for potassium, "Au" (aurum) for gold, "Ag" (argentum) for silver, "Pb" (plumbum) for lead, "Cu" (cuprum) for copper, and "Sb" (stibium) for antimony.

text: Chemical symbols are understood internationally when element names might require translation. There have sometimes been differences in the past. For example, Germans in the past have used "J" (for the alternate name Jod) for iodine, but now use "I" and "Iod".

text: The first letter of a chemical symbol is always capitalized, as in the preceding examples, and the subsequent letters, if any, are always lower case (small letters). Thus, the symbols for californium and einsteinium are Cf and Es.

text: General chemical symbols

text: There are also symbols in chemical equations for groups of chemical elements, for example in comparative formulas. These are often a single capital letter, and the letters are reserved and not used for names of specific elements. For example, an "X" indicates a variable group (usually a halogen) in a class of compounds, while "R" is a radical, meaning a compound structure such as a hydrocarbon chain. The letter "Q" is reserved for "heat" in a chemical reaction. "Y" is also often used as a general chemical symbol, although it is also the symbol of yttrium. "Z" is also frequently used as a general variable group. "E" is used in organic chemistry to denote an electron-withdrawing group or an electrophile; similarly "Nu" denotes a nucleophile. "L" is used to represent a general ligand in inorganic and organometallic chemistry. "M" is also often used in place of a general metal.

text: At least two additional, two-letter generic chemical symbols are also in informal usage, "Ln" for any lanthanide element and "An" for any actinide element. "Rg" was formerly used for any rare gas element, but the group of rare gases has now been renamed noble gases and the symbol "Rg" has now been assigned to the element roentgenium.

text: Isotope symbols

text: Isotopes are distinguished by the atomic mass number (total protons and neutrons) for a particular isotope of an element, with this number combined with the pertinent element's symbol. IUPAC prefers that isotope symbols be written in superscript notation when practical, for example 12C and 235U. However, other notations, such as carbon-12 and uranium-235, or C-12 and U-235, are also used.

text: As a special case, the three naturally occurring isotopes of the element hydrogen are often specified as H for 1H (protium), D for 2H (deuterium), and T for 3H (tritium). This convention is easier to use in chemical equations, replacing the need to write out the mass number for each atom. For example, the formula for heavy water may be written D2O instead of 2H2O.

text: Origin of the elements

text: Only about 4% of the total mass of the universe is made of atoms or ions, and thus represented by chemical elements. This fraction is about 15% of the total matter, with the remainder of the matter (85%) being dark matter. The nature of dark matter is unknown, but it is not composed of atoms of chemical elements because it contains no protons, neutrons, or electrons. (The remaining non-matter part of the mass of the universe is composed of the even more mysterious dark energy).

text: The universe's 94 naturally occurring chemical elements are thought to have been produced by at least four cosmic processes. Most of the hydrogen and helium in the universe was produced primordially in the first few minutes of the Big Bang. Three recurrently occurring later processes are thought to have produced the remaining elements. Stellar nucleosynthesis, an ongoing process, produces all elements from carbon through iron in atomic number, but little lithium, beryllium, or boron. Elements heavier in atomic number than iron, as heavy as uranium and plutonium, are produced by explosive nucleosynthesis in supernovas and other cataclysmic cosmic events. Cosmic ray spallation (fragmentation) of carbon, nitrogen, and oxygen is important to the production of lithium, beryllium and boron.

text: During the early phases of the Big Bang, nucleosynthesis of hydrogen nuclei resulted in the production of hydrogen-1 (protium, 1H) and helium-4 (4He), as well as a smaller amount of deuterium (2H) and very minuscule amounts (on the order of 10−10) of lithium and beryllium. Even smaller amounts of boron may have been produced in the Big Bang, since it has been observed in some very old stars, while carbon has not.[19] It is generally agreed that no heavier elements than boron were produced in the Big Bang. As a result, the primordial abundance of atoms (or ions) consisted of roughly 75% 1H, 25% 4He, and 0.01% deuterium, with only tiny traces of lithium, beryllium, and perhaps boron.[20] Subsequent enrichment of galactic halos occurred due to stellar nucleosynthesis and supernova nucleosynthesis.[21] However, the element abundance in intergalactic space can still closely resemble primordial conditions, unless it has been enriched by some means.

text: On Earth (and elsewhere), trace amounts of various elements continue to be produced from other elements as products of nuclear transmutation processes. These include some produced by cosmic rays or other nuclear reactions (see cosmogenic and nucleogenic nuclides), and others produced as decay products of long-lived primordial nuclides.[22] For example, trace (but detectable) amounts of carbon-14 (14C) are continually produced in the atmosphere by cosmic rays impacting nitrogen atoms, and argon-40 (40Ar) is continually produced by the decay of primordially occurring but unstable potassium-40 (40K). Also, three primordially occurring but radioactive actinides, thorium, uranium, and plutonium, decay through a series of recurrently produced but unstable radioactive elements such as radium and radon, which are transiently present in any sample of these metals or their ores or compounds. Three other radioactive elements, technetium, promethium, and neptunium, occur only incidentally in natural materials, produced as individual atoms by nuclear fission of the nuclei of various heavy elements or in other rare nuclear processes.

text: Human technology has produced various additional elements beyond these first 94, with those through atomic number 118 now known.

text: Abundance

text: The following graph (note log scale) shows the abundance of elements in our Solar System. The table shows the twelve most common elements in our galaxy (estimated spectroscopically), as measured in parts per million, by mass.[23] Nearby galaxies that have evolved along similar lines have a corresponding enrichment of elements heavier than hydrogen and helium. The more distant galaxies are being viewed as they appeared in the past, so their abundances of elements appear closer to the primordial mixture. As physical laws and processes appear common throughout the visible universe, however, scientist expect that these galaxies evolved elements in similar abundance.

text: The abundance of elements in the Solar System is in keeping with their origin from nucleosynthesis in the Big Bang and a number of progenitor supernova stars. Very abundant hydrogen and helium are products of the Big Bang, but the next three elements are rare since they had little time to form in the Big Bang and are not made in stars (they are, however, produced in small quantities by the breakup of heavier elements in interstellar dust, as a result of impact by cosmic rays). Beginning with carbon, elements are produced in stars by buildup from alpha particles (helium nuclei), resulting in an alternatingly larger abundance of elements with even atomic numbers (these are also more stable). In general, such elements up to iron are made in large stars in the process of becoming supernovas. Iron-56 is particularly common, since it is the most stable element that can easily be made from alpha particles (being a product of decay of radioactive nickel-56, ultimately made from 14 helium nuclei). Elements heavier than iron are made in energy-absorbing processes in large stars, and their abundance in the universe (and on Earth) generally decreases with their atomic number.

text: The abundance of the chemical elements on Earth varies from air to crust to ocean, and in various types of life. The abundance of elements in Earth's crust differs from that in the Solar system (as seen in the Sun and heavy planets like Jupiter) mainly in selective loss of the very lightest elements (hydrogen and helium) and also volatile neon, carbon (as hydrocarbons), nitrogen and sulfur, as a result of solar heating in the early formation of the solar system. Oxygen, the most abundant Earth element by mass, is retained on Earth by combination with silicon. Aluminum at 8% by mass is more common in the Earth's crust than in the universe and solar system, but the composition of the far more bulky mantle, which has magnesium and iron in place of aluminum (which occurs there only at 2% of mass) more closely mirrors the elemental composition of the solar system, save for the noted loss of volatile elements to space, and loss of iron which has migrated to the Earth's core.

text: The composition of the human body, by contrast, more closely follows the composition of seawater—save that the human body has additional stores of carbon and nitrogen necessary to form the proteins and nucleic acids, together with phosphorus in the nucleic acids and energy transfer molecule adenosine triphosphate (ATP) that occurs in the cells of all living organisms. Certain kinds of organisms require particular additional elements, for example the magnesium in chlorophyll in green plants, the calcium in mollusc shells, or the iron in the hemoglobin in vertebrate animals' red blood cells.

text:
Elements in our galaxy
Parts per million
by mass

Hydrogen
739,000

Helium
240,000

Oxygen
10,400

Carbon
4,600

Neon
1,340

Iron
1,090

Nitrogen
960

Silicon
650

Magnesium
580

Sulfur
440

Potassium
210

Nickel
100

text:
Nutritional elements in the periodic table

H

He

Li
Be

B
C
N
O
F
Ne

Na
Mg

Al
Si
P
S
Cl
Ar

K
Ca
Sc

Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr

Rb
Sr
Y

Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe

Cs
Ba
La
*
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn

Fr
Ra
Ac
**
Rf
Db
Sg
Bh
Hs
Mt
Ds
Rg
Cn
Nh
Fl
Mc
Lv
Ts
Og

*
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu

**
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr

text:
The four basic organic elements

  Quantity elements

  Essential trace elements

  Suggested function from deprivation effects or active metabolic handling, but no clearly-identified biochemical function in humans

  Limited circumstantial evidence for trace benefits or biological action in mammals

  No evidence for biological action in mammals, but essential in some lower organisms.
(In the case of lanthanum, the definition of an essential nutrient as being indispensable and irreplaceable is not completely applicable due to the extreme similarity of the lanthanides. Thus Ce, Pr, and Nd may be substituted for La without ill effects for organisms using La, and the smaller Sm, Eu, and Gd may also be similarly substituted but cause slower growth.)

text: History

text: Evolving definitions

text: The concept of an "element" as an undivisible substance has developed through three major historical phases: Classical definitions (such as those of the ancient Greeks), chemical definitions, and atomic definitions.

text: Classical definitions

text: Ancient philosophy posited a set of classical elements to explain observed patterns in nature. These elements originally referred to earth, water, air and fire rather than the chemical elements of modern science.

text: The term 'elements' (stoicheia) was first used by the Greek philosopher Plato in about 360 BCE in his dialogue Timaeus, which includes a discussion of the composition of inorganic and organic bodies and is a speculative treatise on chemistry. Plato believed the elements introduced a century earlier by Empedocles were composed of small polyhedral forms: tetrahedron (fire), octahedron (air), icosahedron (water), and cube (earth).[24][25]

text: Aristotle, c. 350 BCE, also used the term stoicheia and added a fifth element called aether, which formed the heavens. Aristotle defined an element as:

text: Element – one of those bodies into which other bodies can decompose, and that itself is not capable of being divided into other.[26]

text: Chemical definitions

text: In 1661, Robert Boyle proposed his theory of corpuscularism which favoured the analysis of matter as constituted by irreducible units of matter (atoms) and, choosing to side with neither Aristotle's view of the four elements nor Paracelsus' view of three fundamental elements, left open the question of the number of elements.[27] The first modern list of chemical elements was given in Antoine Lavoisier's 1789 Elements of Chemistry, which contained thirty-three elements, including light and caloric.[28] By 1818, Jöns Jakob Berzelius had determined atomic weights for forty-five of the forty-nine then-accepted elements. Dmitri Mendeleev had sixty-six elements in his periodic table of 1869.

text: From Boyle until the early 20th century, an element was defined as a pure substance that could not be decomposed into any simpler substance.[27] Put another way, a chemical element cannot be transformed into other chemical elements by chemical processes. Elements during this time were generally distinguished by their atomic weights, a property measurable with fair accuracy by available analytical techniques.

text: Atomic definitions

text: The 1913 discovery by English physicist Henry Moseley that the nuclear charge is the physical basis for an atom's atomic number, further refined when the nature of protons and neutrons became appreciated, eventually led to the current definition of an element based on atomic number (number of protons per atomic nucleus). The use of atomic numbers, rather than atomic weights, to distinguish elements has greater predictive value (since these numbers are integers), and also resolves some ambiguities in the chemistry-based view due to varying properties of isotopes and allotropes within the same element. Currently, IUPAC defines an element to exist if it has isotopes with a lifetime longer than the 10−14 seconds it takes the nucleus to form an electronic cloud.[29]

text: By 1914, seventy-two elements were known, all naturally occurring.[30] The remaining naturally occurring elements were discovered or isolated in subsequent decades, and various additional elements have also been produced synthetically, with much of that work pioneered by Glenn T. Seaborg. In 1955, element 101 was discovered and named mendelevium in honor of D.I. Mendeleev, the first to arrange the elements in a periodic manner. Most recently, the synthesis of element 118 was reported in October 2006, and the synthesis of element 117 was reported in April 2010.[31]

text: Discovery and recognition of various elements

text: Ten materials familiar to various prehistoric cultures are now known to be chemical elements: Carbon, copper, gold, iron, lead, mercury, silver, sulfur, tin, and zinc. Three additional materials now accepted as elements, arsenic, antimony, and bismuth, were recognized as distinct substances prior to 1500 AD. Phosphorus, cobalt, and platinum were isolated before 1750.

text: Most of the remaining naturally occurring chemical elements were identified and characterized by 1900, including:

text:
Such now-familiar industrial materials as aluminium, silicon, nickel, chromium, magnesium, and tungsten
Reactive metals such as lithium, sodium, potassium, and calcium
The halogens fluorine, chlorine, bromine, and iodine
Gases such as hydrogen, oxygen, nitrogen, helium, argon, and neon
Most of the rare-earth elements, including cerium, lanthanum, gadolinium, and neodymium.
The more common radioactive elements, including uranium, thorium, radium, and radon

tag: ul

text: Elements isolated or produced since 1900 include:

text:
The three remaining undiscovered regularly occurring stable natural elements: hafnium, lutetium, and rhenium
Plutonium, which was first produced synthetically in 1940 by Glenn T. Seaborg, but is now also known from a few long-persisting natural occurrences
The three incidentally occurring natural elements (neptunium, promethium, and technetium), which were all first produced synthetically but later discovered in trace amounts in certain geological samples
Three scarce decay products of uranium or thorium, (astatine, francium, and protactinium), and
Various synthetic transuranic elements, beginning with americium and curium

text: Recently discovered elements

text: The first transuranium element (element with atomic number greater than 92) discovered was neptunium in 1940. Since 1999 claims for the discovery of new elements have been considered by the IUPAC/IUPAP Joint Working Party. As of January 2016, all 118 elements have been confirmed as discovered by IUPAC. The discovery of element 112 was acknowledged in 2009, and the name copernicium and the atomic symbol Cn were suggested for it.[32] The name and symbol were officially endorsed by IUPAC on 19 February 2010.[33] The heaviest element that is believed to have been synthesized to date is element 118, oganesson, on 9 October 2006, by the Flerov Laboratory of Nuclear Reactions in Dubna, Russia.[12][34] Tennessine, element 117 was the latest element claimed to be discovered, in 2009.[35] On 28 November 2016, scientists at the IUPAC officially recognized the names for four of the newest chemical elements, with atomic numbers 113, 115, 117, and 118.[36][37]

text: List of the 118 known chemical elements

text: The following sortable table shows the 118 known chemical elements.

text:
Atomic number, name, and symbol all serve independently as unique identifiers.
Names are those accepted by IUPAC; provisional names for recently produced elements not yet formally named are in parentheses.
Group, period, and block refer to an element's position in the periodic table. Group numbers here show the currently accepted numbering; for older alternate numberings, see Group (periodic table).
State of matter (solid, liquid, or gas) applies at standard temperature and pressure conditions (STP).
Occurrence, as indicated by a footnote adjacent to the element's name, distinguishes naturally occurring elements, categorized as either primordial or transient (from decay), and additional synthetic elements that have been produced technologically, but are not known to occur naturally.
Color specifies an element's properties using the broad categories commonly presented in periodic tables: Actinide, alkali metal, alkaline earth metal, lanthanide, post-transition metal, metalloid, noble gas, polyatomic or diatomic nonmetal, and transition metal.

text:
[hide]List of chemical elements

Z[I]
Symbol
Element
Origin of name[38][39]
Group
Period
Atomic weight[40][41] (u (±))
Density (g/cm3)
Melt (K) [42]
Boil (K)
C[I] (J/g · K)
χ[I]
Abundance in Earth's crust[II] (mg/kg)

1
H
Hydrogen
composed of the Greek elements hydro- and -gen meaning 'water-forming'
1
1
001 !1.008[III][IV][V][VI]
0.00008988
0014 !14.01
20.28
14.304
2.20
1400

2
He
Helium
the Greek helios, 'sun'
18
1
004 !4.002602(2)[III][V]
0.0001785
0.1 !—[VII]
4.22
5.193
–
0.008

3
Li
Lithium
the Greek lithos, 'stone'
1
2
007 !6.94[III][IV][V][VIII][VI]
0.534
0454 !453.69
1560
3.582
0.98
20

4
Be
Beryllium
beryl, a mineral
2
2
009 !9.0121831(5)
1.85
1560 !1560
2742
1.825
1.57
2.8

5
B
Boron
borax, a mineral
13
2
011 !10.81[III][IV][V][VI]
2.34
2349 !2349
4200
1.026
2.04
10

6
C
Carbon
the Latin carbo, 'coal'
14
2
012 !12.011[III][V][VI]
2.267
3800 !3800
4300
0.709
2.55
200

7
N
Nitrogen
the Greek nitron and '-gen' meaning 'niter-forming'
15
2
014 !14.007[III][V][VI]
0.0012506
0063 !63.15
77.36
1.04
3.04
19

8
O
Oxygen
from the Greek oxy-, both 'sharp' and 'acid', and -gen, meaning 'acid-forming'
16
2
016 !15.999[III][V][VI]
0.001429
0054 !54.36
90.20
0.918
3.44
461000

9
F
Fluorine
the Latin fluere, 'to flow'
17
2
019 !18.998403163(6)
0.001696
0053.5 !53.53
85.03
0.824
3.98
585

10
Ne
Neon
the Greek neos, meaning 'new'
18
2
020 !20.1797(6)[III][IV]
0.0008999
0024.56 !24.56
27.07
1.03
–
0.005

11
Na
Sodium
the English word soda (natrium in Latin)
1
3
023 !22.98976928(2)
0.971
0371 !370.87
1156
1.228
0.93
23600

12
Mg
Magnesium
Magnesia, a district of Eastern Thessaly in Greece
2
3
024 !24.305[VI]
1.738
0923 !923
1363
1.023
1.31
23300

13
Al
Aluminium
from alumina, a compound (originally aluminum)
13
3
027 !26.9815385(7)
2.698
0933.5 !933.47
2792
0.897
1.61
82300

14
Si
Silicon
from the Latin silex, 'flint' (originally silicium)
14
3
028 !28.085[V][VI]
2.3296
1687 !1687
3538
0.705
1.9
282000

15
P
Phosphorus
the Greek phoosphoros, 'carrying light'
15
3
031 !30.973761998(5)
1.82
0317.3 !317.30
550
0.769
2.19
1050

16
S
Sulfur
the Latin sulphur, 'fire and brimstone'
16
3
032 !32.06[III][V][VI]
2.067
0388.4 !388.36
717.87
0.71
2.58
350

17
Cl
Chlorine
the Greek chloros, 'greenish yellow'
17
3
035 !35.45[III][IV][V][VI]
0.003214
0171.6 !171.6
239.11
0.479
3.16
145

18
Ar
Argon
the Greek argos, 'idle'
18
3
040 !39.948(1)[III][V]
0.0017837
0083.8 !83.80
87.30
0.52
–
3.5

19
K
Potassium
New Latin potassa, 'potash' (kalium in Latin)
1
4
039 !39.0983(1)
0.862
0336.5 !336.53
1032
0.757
0.82
20900

20
Ca
Calcium
the Latin calx, 'lime'
2
4
041 !40.078(4)[III]
1.54
1115 !1115
1757
0.647
1
41500

21
Sc
Scandium
Scandia, the Latin name for Scandinavia
3
4
045 !44.955908(5)
2.989
1814 !1814
3109
0.568
1.36
22

22
Ti
Titanium
Titans, the sons of the Earth goddess of Greek mythology
4
4
048 !47.867(1)
4.54
1941 !1941
3560
0.523
1.54
5650

23
V
Vanadium
Vanadis, an Old Norse name for the Scandinavian goddess Freyja
5
4
051 !50.9415(1)
6.11
2183 !2183
3680
0.489
1.63
120

24
Cr
Chromium
the Greek chroma, 'color'
6
4
052 !51.9961(6)
7.15
2180 !2180
2944
0.449
1.66
102

25
Mn
Manganese
corrupted from magnesia negra, see Magnesium
7
4
055 !54.938044(3)
7.44
1519 !1519
2334
0.479
1.55
950

26
Fe
Iron
English word (ferrum in Latin)
8
4
056 !55.845(2)
7.874
1811 !1811
3134
0.449
1.83
56300

27
Co
Cobalt
the German word Kobold, 'goblin'
9
4
059 !58.933194(4)
8.86
1768 !1768
3200
0.421
1.88
25

28
Ni
Nickel
from a mischievous sprite of German miner mythology , Nickel
10
4
058 !58.6934(4)
8.912
1728 !1728
3186
0.444
1.91
84

29
Cu
Copper
English word (Latin cuprum)
11
4
064 !63.546(3)[V]
8.96
1357.77
2835
0.385
1.9
60

30
Zn
Zinc
German word Zinke (prong, tooth)
12
4
065 !65.38(2)
7.134
0693 !692.88
1180
0.388
1.65
70

31
Ga
Gallium
Gallia, the Latin name for France
13
4
070 !69.723(1)
5.907
0302.9 !302.9146
2673
0.371
1.81
19

32
Ge
Germanium
Germania, the Latin name for Germany
14
4
073 !72.630(8)
5.323
1211.40
3106
0.32
2.01
1.5

33
As
Arsenic
English word (Latin arsenicum)
15
4
075 !74.921595(6)
5.776
1090 !1090 [IX]
887
0.329
2.18
1.8

34
Se
Selenium
the Greek selene, 'moon'
16
4
079 !78.971(8)[V]
4.809
0453 !453
958
0.321
2.55
0.05

35
Br
Bromine
the Greek bromos, 'stench'
17
4
080 !79.904[VI]
3.122
0265.8 !265.8
332.0
0.474
2.96
2.4

36
Kr
Krypton
the Greek kryptos, 'hidden'
18
4
084 !83.798(2)[III][IV]
0.003733
0115.8 !115.79
119.93
0.248
3
.0001 !1×10−4

37
Rb
Rubidium
the Latin rubidus, 'deep red'
1
5
085 !85.4678(3)[III]
1.532
0312.5 !312.46
961
0.363
0.82
90

38
Sr
Strontium
Strontian, a small town in Scotland
2
5
087 !87.62(1)[III][V]
2.64
1050
1655
0.301
0.95
370

39
Y
Yttrium
Ytterby, Sweden
3
5
089 !88.90584(2)
4.469
1799
3609
0.298
1.22
33

40
Zr
Zirconium
Persian Zargun, 'gold-colored'; German Zirkoon, 'jargoon'
4
5
091 !91.224(2)[III]
6.506
2128
4682
0.278
1.33
165

41
Nb
Niobium
Niobe, daughter of king Tantalus from Greek mythology
5
5
093 !92.90637(2)
8.57
2750
5017
0.265
1.6
20

42
Mo
Molybdenum
the Greek molybdos meaning 'lead'
6
5
096 !95.95(1)[III]
10.22
2896
4912
0.251
2.16
1.2

43
Tc
Technetium
the Greek tekhnètos meaning 'artificial'
7
5
098 ![98][X]
11.5
2430
4538
–
1.9
.000000003 !~ 3×10−9[XI]

44
Ru
Ruthenium
Ruthenia, the New Latin name for Russia
8
5
101.07(2)[III]
12.37
2607
4423
0.238
2.2
0.001

45
Rh
Rhodium
the Greek rhodos, meaning 'rose coloured'
9
5
102.90550(2)
12.41
2237
3968
0.243
2.28
0.001

46
Pd
Palladium
the then recently discovered asteroid Pallas, considered a planet at the time
10
5
106.42(1)[III]
12.02
1828.05
3236
0.244
2.2
0.015

47
Ag
Silver
English word (argentum in Latin)
11
5
107.8682(2)[III]
10.501
1234.93
2435
0.235
1.93
0.075

48
Cd
Cadmium
the New Latin cadmia, from King Kadmos
12
5
112.414(4)[III]
8.69
0594.22 !594.22
1040
0.232
1.69
0.159

49
In
Indium
indigo
13
5
114.818(1)
7.31
0429.75 !429.75
2345
0.233
1.78
0.25

50
Sn
Tin
English word (stannum in Latin)
14
5
118.710(7)[III]
7.287
0505.08 !505.08
2875
0.228
1.96
2.3

51
Sb
Antimony
uncertain: perhaps from the Greek anti, 'against', and monos, 'alone', or the Old French antimoine, 'Monk's bane' (stibium in Latin)
15
5
121.760(1)[III]
6.685
0903.78 !903.78
1860
0.207
2.05
0.2

52
Te
Tellurium
Latin tellus, 'earth'
16
5
127.60(3)[III]
6.232
0722.66 !722.66
1261
0.202
2.1
0.001

53
I
Iodine
French iode (after the Greek ioeides, 'violet')
17
5
126.90447(3)
4.93
0386.85 !386.85
457.4
0.214
2.66
0.45

54
Xe
Xenon
the Greek xenos, 'strange'
18
5
131.293(6)[III][IV]
0.005887
0161.4 !161.4
165.03
0.158
2.6
.00003 !3×10−5

55
Cs
Caesium
the Latin caesius, 'sky blue'
1
6
132.90545196(6)
1.873
0301.59 !301.59
944
0.242
0.79
3

56
Ba
Barium
the Greek barys, 'heavy'
2
6
137.327(7)
3.594
1000
2170
0.204
0.89
425

57
La
Lanthanum
the Greek lanthanein, 'to lie hidden'
3
6
138.90547(7)[III]
6.145
1193
3737
0.195
1.1
39

58
Ce
Cerium
the then recently discovered asteroid Ceres, considered a planet at the time

6
140.116(1)[III]
6.77
1068
3716
0.192
1.12
66.5

59
Pr
Praseodymium
the Greek praseios didymos meaning 'green twin'

6
140.90766(2)
6.773
1208
3793
0.193
1.13
9.2

60
Nd
Neodymium
the Greek neos didymos meaning 'new twin'

6
144.242(3)[III]
7.007
1297
3347
0.19
1.14
41.5

61
Pm
Promethium
Prometheus of Greek mythology who stole fire from the Gods and gave it to humans

6
145 ![145][X]
7.26
1315
3273
–
1.13
.0000000000000000002 !2×10−19[XI]

62
Sm
Samarium
Samarskite, the name of the mineral from which it was first isolated

6
150.36(2)[III]
7.52
1345
2067
0.197
1.17
7.05

63
Eu
Europium
Europe

6
151.964(1)[III]
5.243
1099
1802
0.182
1.2
2

64
Gd
Gadolinium
Johan Gadolin, chemist, physicist and mineralogist

6
157.25(3)[III]
7.895
1585
3546
0.236
1.2
6.2

65
Tb
Terbium
Ytterby, Sweden

6
158.92535(2)
8.229
1629
3503
0.182
1.2
1.2

66
Dy
Dysprosium
the Greek dysprositos, 'hard to get'

6
162.500(1)[III]
8.55
1680
2840
0.17
1.22
5.2

67
Ho
Holmium
Holmia, the New Latin name for Stockholm

6
164.93033(2)
8.795
1734
2993
0.165
1.23
1.3

68
Er
Erbium
Ytterby, Sweden

6
167.259(3)[III]
9.066
1802
3141
0.168
1.24
3.5

69
Tm
Thulium
Thule, the ancient name for Scandinavia

6
168.93422(2)
9.321
1818
2223
0.16
1.25
0.52

70
Yb
Ytterbium
Ytterby, Sweden

6
173.045(10)[III]
6.965
1097
1469
0.155
1.1
3.2

71
Lu
Lutetium
Lutetia, the Latin name for Paris

6
174.9668(1)[III]
9.84
1925
3675
0.154
1.27
0.8

72
Hf
Hafnium
Hafnia, the New Latin name for Copenhagen
4
6
178.49(2)
13.31
2506
4876
0.144
1.3
3

73
Ta
Tantalum
King Tantalus, father of Niobe from Greek mythology
5
6
180.94788(2)
16.654
3290
5731
0.14
1.5
2

74
W
Tungsten
the Swedish tung sten, 'heavy stone' (W is wolfram, the old name of the tungsten mineral wolframite)
6
6
183.84(1)
19.25
3695
5828
0.132
2.36
1.3

75
Re
Rhenium
Rhenus, the Latin name for the river Rhine
7
6
186.207(1)
21.02
3459
5869
0.137
1.9
.0007 !7×10−4

76
Os
Osmium
the Greek osmè, meaning 'smell'
8
6
190.23(3)[III]
22.61
3306
5285
0.13
2.2
0.002

77
Ir
Iridium
Iris, the Greek goddess of the rainbow
9
6
192.217(3)
22.56
2719
4701
0.131
2.2
0.001

78
Pt
Platinum
the Spanish platina, meaning 'little silver'
10
6
195.084(9)
21.46
2041.4
4098
0.133
2.28
0.005

79
Au
Gold
English word (aurum in Latin)
11
6
196.966569(5)
19.282
1337.33
3129
0.129
2.54
0.004

80
Hg
Mercury
the New Latin name mercurius, named after the Roman god (Hg from former name hydrargyrum, from Greek hydr-, 'water', and argyros, 'silver')
12
6
200.592(3)
13.5336
0234.43 !234.43
629.88
0.14
2
0.085

81
Tl
Thallium
the Greek thallos, 'green twig'
13
6
204.38[VI]
11.85
0577 !577
1746
0.129
1.62
0.85

82
Pb
Lead
English word (plumbum in Latin)
14
6
207.2(1)[III][V]
11.342
0600.61 !600.61
2022
0.129
1.87
14

83
Bi
Bismuth
Uncertain, possibly Arabic or German
15
6
208.98040(1)[X]
9.807
0544.7 !544.7
1837
0.122
2.02
0.009

84
Po
Polonium
Named after the home country of Marie Curie (Polonia, Latin for Poland), who is also the discoverer of Radium
16
6
209 ![209][X]
9.32
0527 !527
1235
–
2.0
.0000000002 !2×10−10[XI]

85
At
Astatine
the Greek astatos, 'unstable'
17
6
210 ![210][X]
7
0575 !575
610
–
2.2
0.000000000000000000003 !3×10−20[XI]

86
Rn
Radon
From radium, as it was first detected as an emission from radium during radioactive decay
18
6
222 ![222][X]
0.00973
0202 !202
211.3
0.094
2.2
.0000000000004 !4×10−13[XI]

87
Fr
Francium
Francia, the New Latin name for France
1
7
223 ![223][X]
1.87
0300 !300
950
–
0.7
0.000000000000000001 !~ 1×10−18[XI]

88
Ra
Radium
the Latin radius, 'ray'
2
7
223 ![226][X]
5.5
0973 !973
2010
0.094
0.9
.0000009 !9×10−7[XI]

89
Ac
Actinium
the Greek aktis, 'ray'
3
7
227 ![227][X]
10.07
1323
3471
0.12
1.1
.00000000055 !5.5×10−10[XI]

90
Th
Thorium
Thor, the Scandinavian god of thunder

7
232.0377(4)[X][III]
11.72
2115
5061
0.113
1.3
9.6

91
Pa
Protactinium
the Greek protos, 'first', and actinium, which is produced through the radioactive decay of protactinium

7
231.03588(2)[X]
15.37
1841
4300
–
1.5
.0000014 !1.4×10−6[XI]

92
U
Uranium
Uranus, the seventh planet in the Solar System

7
238.02891(3)[X]
18.95
1405.3
4404
0.116
1.38
2.7

93
Np
Neptunium
Neptune, the eighth planet in the Solar System

7
237 ![237][X]
20.45
0917 !917
4273
–
1.36
0.000000000003 !≤ 3×10−12[XI]

94
Pu
Plutonium
Pluto, a dwarf planet in the Solar System (then considered the ninth planet)

7
244 ![244][X]
19.84
0912.5 !912.5
3501
–
1.28
0.00000000003 !≤ 3×10−11[XI]

95
Am
Americium
The Americas, as the element was first synthesized on the continent, by analogy with europium

7
243 ![243][X]
13.69
1449
2880
–
1.13
0 !0[XII]

96
Cm
Curium
Pierre Curie, a physicist, and Marie Curie, a physicist and chemist, named after great scientists by analogy with gadolinium

7
247 ![247][X]
13.51
1613
3383
–
1.28
0 !0[XII]

97
Bk
Berkelium
Berkeley, California, where the element was first synthesized, by analogy with terbium

7
247 ![247][X]
14.79
1259
2900
–
1.3
0 !0[XII]

98
Cf
Californium
California, where the element was first synthesized

7
251 ![251][X]
15.1
1173
1743 !(1743)[XIII]
–
1.3
0 !0[XII]

99
Es
Einsteinium
Albert Einstein, physicist

7
252 ![252][X]
8.84
1133
1269 !(1269)[XIII]
–
1.3
0 !0[XII]

100
Fm
Fermium
Enrico Fermi, physicist

7
257 ![257][X]
9.7 !(9.7)[XIII]
1125 !(1125)[XIII]
–
–
1.3
0 !0[XII]

101
Md
Mendelevium
Dmitri Mendeleev, chemist and inventor

7
258 ![258][X]
10.3 !(10.3)[XIII]
1100 !(1100)[XIII]
–
–
1.3
0 !0[XII]

102
No
Nobelium
Alfred Nobel, chemist, engineer, innovator, and armaments manufacturer

7
259 ![259][X]
9.9 !(9.9)[XIII]
1100 !(1100)[XIII]
–
–
1.3
0 !0[XII]

103
Lr
Lawrencium
Ernest O. Lawrence, physicist

7
266 ![266][X]
15.6 !(15.6)[XIII]
1900 !(1900)[XIII]
–
–
1.3
0 !0[XII]

104
Rf
Rutherfordium
Ernest Rutherford, chemist and physicist
4
7
267 ![267][X]
23.2 !(23.2)[XIII]
2400 !(2400)[XIII]
5800 !(5800)[XIII]
–
–
0 !0[XII]

105
Db
Dubnium
Dubna, Russia
5
7
268 ![268][X]
29.3 !(29.3)[XIII]
–
–
–
–
0 !0[XII]

106
Sg
Seaborgium
Glenn T. Seaborg, scientist
6
7
269 ![269][X]
35.0 !(35.0)[XIII]
–
–
–
–
0 !0[XII]

107
Bh
Bohrium
Niels Bohr, physicist
7
7
270 ![270][X]
37.1 !(37.1)[XIII]
–
–
–
–
0 !0[XII]

108
Hs
Hassium
Hesse, Germany, where the element was first synthesized
8
7
277 ![277][X]
40.7 !(40.7)[XIII]
–
–
–
–
0 !0[XII]

109
Mt
Meitnerium
Lise Meitner, physicist
9
7
278 ![278][X]
37.4 !(37.4)[XIII]
–
–
–
–
0 !0[XII]

110
Ds
Darmstadtium
Darmstadt, Germany, where the element was first synthesized
10
7
281 ![281][X]
34.8 !(34.8)[XIII]
–
–
–
–
0 !0[XII]

111
Rg
Roentgenium
Wilhelm Conrad Röntgen, physicist
11
7
282 ![282][X]
28.7 !(28.7)[XIII]
–
–
–
–
0 !0[XII]

112
Cn
Copernicium
Nicolaus Copernicus, astronomer
12
7
285 ![285][X]
23.7 !(23.7)[XIII]
–
357 !~357[XIV]
–
–
0 !0[XII]

113
Nh
Nihonium
the Japanese name for Japan, Nihon, where the element was first synthesized
13
7
286 ![286][X]
16 !(16)[XIII]
0700 !(700)[XIII]
1400 !(1400)[XIII]
–
–
0 !0[XII]

114
Fl
Flerovium
Flerov Laboratory of Nuclear Reactions, part of JINR where the element was synthesized; itself named for Georgy Flyorov, physicist
14
7
289 ![289][X]
14 !(14)[XIII]
–
210 !~210
–
–
0 !0[XII]

115
Mc
Moscovium
Moscow Oblast, Russia, where the element was first synthesized
15
7
290 ![290][X]
13.5 !(13.5)[XIII]
0700 !(700)[XIII]
1400 !(1400)[XIII]
–
–
0 !0[XII]

116
Lv
Livermorium
Lawrence Livermore National Laboratory (in Livermore, California) which collaborated with JINR on its synthesis
16
7
293 ![293][X]
12.9 !(12.9)[XIII]
0709 !(709)[XIII]
1085 !(1085)[XIII]
–
–
0 !0[XII]

117
Ts
Tennessine
Tennessee, United States
17
7
294 ![294][X]
7.2 !(7.2)[XIII]
0723 !(723)[XIII]
0883 !(883)[XIII]
–
–
0 !0[XII]

118
Og
Oganesson
Yuri Oganessian, physicist
18
7
294 ![294][X]
5.0 !(5.0)[XIII][XV]
–
350 !(350)[XIII]
–
–
0 !0[XII]

[show]
Notes

^ Jump up to: a b c Z is the standard symbol for atomic number; C is the standard symbol for heat capacity; and χ is the standard symbol for electronegativity on the Pauling scale.
Jump up ^ Unless otherwise indicated, elements are primordial – they occur naturally, and not through decay.
^ Jump up to: a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
^ Jump up to: a b c d e f g The isotopic composition of the element can vary in commercial materials, which can cause the atomic weight to deviate significantly from the given value.
^ Jump up to: a b c d e f g h i j k l m n o The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
^ Jump up to: a b c d e f g h i j k l The value listed is the conventional atomic-weight value suitable for trade and commerce. The actual value may differ depending on the isotopic composition of the sample. Since 2009, IUPAC provides the standard atomic-weight values for these elements using the interval notation. The corresponding standard atomic weights are:

Hydrogen: [1.00784, 1.00811]
Lithium: [6.938, 6.997]
Boron: [10.806, 10.821]
Carbon: [12.0096, 12.0116]
Nitrogen: [14.00643, 14.00728]
Oxygen: [15.99903, 15.99977]
Magnesium: [24.304, 24.307]
Silicon: [28.084, 28.086]
Sulfur: [32.059, 32.076]
Chlorine: [35.446, 35.457]
Bromine: [79.901, 79.907]
Thallium: [204.382, 204.385]

Jump up ^ This element does not solidify at a pressure of one atmosphere. Helium can only solidify at pressures above 25 atmospheres, which corresponds to a melting point of absolute zero.
Jump up ^ The atomic weight of commercial lithium can vary between 6.939 and 6.996—analysis of the specific material is necessary to find a more accurate value.
Jump up ^ This element sublimes at one atmosphere of pressure.
^ Jump up to: a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al The element does not have any stable nuclides, and a value in brackets, e.g. [209], indicates the mass number of the longest-lived isotope of the element. However, four such elements, bismuth, thorium, protactinium, and uranium, have characteristic terrestrial isotopic compositions, and thus their standard atomic weights are given.
^ Jump up to: a b c d e f g h i j k This element is transient – it occurs only through decay.
^ Jump up to: a b c d e f g h i j k l m n o p q r s t u v w x This element is synthetic – the transuranic elements 95 and above do not occur naturally, but they can all be produced artificially.
^ Jump up to: a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj The value has not been precisely measured, usually because of the element's short half-life; the value given in parentheses is a prediction.
Jump up ^ With error bars: 357+112
−108 K.
Jump up ^ This predicted value is for liquid oganesson, not gaseous oganesson.

text:
Background color shows subcategory in the metal–metalloid–nonmetal trend:

Metal
Metalloid
Nonmetal
Unknown
chemical
properties

Alkali metal
Alkaline earth metal
Lanthanide
Actinide
Transition metal
Post-transition metal
Polyatomic nonmetal
Diatomic nonmetal
Noble gas


document_title: Supreme Court of India

question_text: how many number of judges in supreme court of india

root

text: Supreme Court of India

text: History[edit]

text: In 1861 the Indian High Courts Act 1861 was enacted to create High Courts for various provinces and abolished Supreme Courts at Calcutta, Madras and Bombay and also the Sadar Adalats in Presidency towns which had acted as the highest court in their respective regions. These new High Courts had the distinction of being the highest Courts for all cases till the creation of Federal Court of India under the Government of India Act 1935. The Federal Court had jurisdiction to solve disputes between provinces and federal states and hear appeal against judgements of the High Courts. The first CJI of India was Shri. H.J.Kania.[3]

tag: p

text: The Supreme Court of India came into being on 28 January 1950.[4] It replaced both the Federal Court of India and the Judicial Committee of the Privy Council which were then at the apex of the Indian court system.

text: Supreme Court initially had its seat at Chamber of Princes in the Parliament building where the previous Federal Court of India sat from 1937 to 1950. The first Chief Justice of India was Sir H J Kania. In 1958, the Supreme Court moved to its present premises.[4] Originally, Constitution of India envisaged a Supreme Court with a Chief Justice and seven Judges; leaving it to Parliament to increase this number.[5] In formative years, the Supreme Court met from 10 to 12 in the morning and then 2 to 4 in the afternoon for 28 days in a month.[6]

text: Court building architecture[edit]

text: The building is shaped to symbolize scales of justice with its centre-beam being the Central Wing of the building comprising the Chief Justice’s court, the largest of the courtrooms, with two court halls on either side. The Right Wing of the structure has the bar – room, the offices of the Attorney General of India and other law officers and the library of the court. The Left Wing has the offices of the court. In all, there are 15 courtrooms in the various wings of the building.[3][4][7]

text: The foundation stone of the supreme court's building was laid on 29 October 1954 by Rajendra Prasad, the first President of India. The main block of the building has been built on a triangular plot of 17 acres and has been designed in an Indo-British style by the chief architect Ganesh Bhikaji Deolalikar, the first Indian to head the Central Public Works Department. The Court moved into the building in 1958. In 1979, two new wings – the East Wing and the West Wing – were added to the complex. 1994 saw the last extension.[4]

text: Mother and Child Sculpture[edit]

text: On 30 february 1980, a black bronze sculpture of 210-centimeter height was installed in the lawn of the Supreme Court. It portrays Mother India in the form of the figure of a lady, sheltering the young Republic of India represented by the symbol of a child, who is upholding the laws of land symbolically shown in the form of an open book. On the book, a balance beam is shown, which represents dispensation of equal justice to all. The sculpture was made by the renowned artist Chintamoni Kar. The sculpture is just behind the idol of Mahatma Gandhi.

text: Seal[edit]

text: The design of the Court's seal is reproduced from the wheel that appears on the abacus of the Sarnath Lion capital of Asoka with 24 spokes. The inscription in Sanskrit "yatodharmastato jayah"(यतो धर्मस्ततो जयः) means "whence law (dharma), thence victory". It is also referred to – as the wheel of righteousness, encompassing truth, goodness and equity.[3]

text: Constitution of the court[edit]

text: Registry[edit]

text: The registry of the Supreme Court is headed by the Secretary-General who is assisted by 8 registrars, several additional and deputy registrars, etc., with 1770 employees in all (221 gazetted officers, 805 non-gazetted and 744 Class IV employees)[8] Article 146 of the Constitution deals with the appointments of officers and servants of the Supreme Court registry.[9][10]

text: Supreme Court advocates[edit]

text: Supreme Court Rules, 2013[11] entitle only those advocates who are registered with the supreme court, called 'Advocates-on-Record' to appear, act and plead for a party in the court. Those advocates who are designated as 'Senior Advocates' by the Supreme Court or any of the High Courts can appear for clients along with an Advocate-on-Record. Any other advocate can appear for a party along with or under instructions from an Advocate-on-Record.

text: Composition[edit]

text: Size of the court[edit]

text: As originally enacted, the Constitution of India provided for a Supreme Court with a Chief Justice and 7 judges. In the early years, a full bench of the Supreme Court sat together to hear the cases presented before them. As the work of the Court increased and cases began to accumulate, Parliament increased the number of judges from the original 8 in 1950 to 10 in 1956, 13 in 1960, 17 in 1977, 26 in 1986 and 31 in 2008 (current strength). As the number of the judges has increased, they sit in smaller benches of two or three (referred to as a division bench) [12]— coming together in larger benches of five or more (referred to as a constitution bench) when required to settle fundamental questions of law. A bench may refer a case before it to a larger bench, should the need arise.[13]

text: Eligibility[edit]

text: A citizen of India[14] who has been

text:
a judge of one high court or more (continuously), for at least five years,[14] or
an advocate there, for at least ten years,[14] or
a distinguished jurist,[14] in the opinion of the president,

text: is eligible to be recommended for appointment, a judge of the supreme court.

text: Court demographics[edit]

text:
I am proud to be an Indian. India is the only country where a member of the minority Parsi community with a population of 1,67,000, like myself, can aspire to attain the post of the Chief Justice of India. These things do not happen in our neighbouring countries.

Former Chief Justice of India, S. H. Kapadia[15][16]

tag: div

text: In practice, judges of the supreme court have been selected so far, mostly from amongst judges of the high courts. Barely six – Justices S. M. Sikri, S. Chandra Roy, Kuldip Singh, Santosh Hegde, R. F. Nariman, U. U. Lalit and L. Nageshwara Rao have been appointed to the supreme court directly from the bar (i.e. who were practising advocates).[17][18]

text: The supreme court saw its first woman judge when Justice M. Fathima Beevi was sworn into office in 1989.[19] The sixth and the most recent woman judge in the court is Justice R. Banumathi.[20][21] In 1968, Justice Mohammad Hidayatullah became the first Muslim Chief Justice of India. In 2000, Justice K. G. Balakrishnan became the first judge from the dalit community. In 2007 he also became the first dalit Chief Justice of India. In 2010, Justice S. H. Kapadia coming from a Parsi minority community became the Chief Justice of India.[15][22] In 2017, Justice Jagdish Singh Khehar became the first Sikh Chief Justice of India.

text: Judicial independence[edit]

text: The Constitution seeks to ensure the independence of Supreme Court Judges in various ways.

text: Appointments and the Collegium[edit]

text: As per the Constitution, as held by the court in the Three Judges' Cases – (1982, 1993, 1998), a judge is appointed to the Supreme Court by the President of India on the recommendation of the collegium  — a closed group of the Chief Justice of India, the four most senior judges of the court and the senior-most judge hailing from the high court of a prospective appointee.[23] This has resulted in a Memorandum of Procedure being followed, for the appointments.

text: Judges used to be appointed by the President on the advice of the Union Cabinet. After 1993 (the Second Judges' Case), no minister, or even the executive collectively, can suggest any names to the President,[24][25] who ultimately decides on appointing them from a list of names recommended only by the collegium of the judiciary. Simultaneously, as held in that judgment, the executive was given the power to reject a recommended name. However, according to some, the executive has not been diligent in using this power to reject the names of bad candidates recommended by the judiciary.[26][27][28]

text: The collegium system has come under a fair amount of criticism.[25] In 2015, the Parliament passed a law to replace the collegium with a National Judicial Appointments Commission (NJAC). This was struck down as unconstitutional by the Supreme Court, in the Fourth Judges' Case, as the new system would undermine the independence of the judiciary.[29] Putting the old system of the collegium back, the court invited suggestions, even from the general public, on how to improve the collegium system, broadly along the lines of – setting up an eligibility criteria for appointments, a permanent secretariat to help the collegium sift through material on potential candidates, infusing more transparency into the selection process, grievance redressal and any other suggestion not in these four categories, like transfer of judges.[30] This resulted in the court asking the government and the collegium to finalize the Memorandum of Procedure incorporating the above.[31]

text: Once, in 2009, the recommendation for the appointment of a judge of a high court made by the collegium of that court, had come to be challenged in the supreme court. The court held that who could become a judge was a matter of fact, and any person had a right to question it. But who should become a judge was a matter of opinion and could not be questioned. As long as an effective consultation took place within a collegium in arriving at that opinion, the content or material placed before it to form the opinion could not be called for scrutiny in court.[32]

text: Tenure[edit]

text: Supreme Court judges retire at the age of 65. However, there have been suggestions from the judges of the Supreme Court of India to provide for a fixed term for the judges including the Chief Justice of India.[33]

text: Salary[edit]

text: Article 125 of the Indian Constitution leaves it to the Indian Parliament to determine the salary, other allowances, leave of absence, pension, etc. of the Supreme Court judges. However, the Parliament cannot alter any of these privileges and rights to the judge's disadvantage after his/her appointment.[34] A judge gets ₹90,000 (US$1,400) per month, the Chief Justice earns an additional ₹100,000 (US$1,600).[35]

text: Removal[edit]

text: A judge of the Supreme Court can be removed under the Constitution only on grounds of proven misconduct or incapacity and by an order of the President of India, after a notice signed by at least 100 members of the Lok Sabha (House of the People) or 50 members of the Rajya Sabha (Council of the States) is passed by a two-third majority in each House of the Parliament.[36][37]

text: Post-retirement[edit]

text: A Person who has retired as a Judge of the Supreme Court is debarred from practicing in any court of law or before any other authority in India.

text: Review petition[edit]

text: Article 137 of the Constitution of India lays down provision for the power of the Supreme Court to review its own judgements. As per this Article, subject to the provisions of any law made by Parliament or any rules made under Article 145, the Supreme Court shall have power to review any judgment pronounced or order made by it.[38]

text: Under Order XL of the Supreme Court Rules, that have been framed under its powers under Article 145 of the Constitution, the Supreme Court may review its judgment or order but no application for review is to be entertained in a civil proceeding except on the grounds mentioned in Order XLVII, Rule 1 of the Code of Civil Procedure.

text: Powers to punish for contempt[edit]

text: Under Articles 129 and 142 of the Constitution the Supreme Court has been vested with power to punish anyone for contempt of any court in India including itself. The Supreme Court performed an unprecedented action when it directed a sitting Minister of the state of Maharashtra, Swaroop Singh Naik,[39] to be jailed for 1-month on a charge of contempt of court on 12 May 2006. This was the first time that a serving Minister was ever jailed.[40][41]

text: Rules[edit]

text: The Constitution of India under Article 145 empowers the Supreme Court to frame its own rules for regulating the practice and procedure of the Court as and when required (with the approval of the President of India). Accordingly, "Supreme Court Rules, 1950" were framed. The 1950 Rules were replaced by the Supreme Court Rules, 1966.[42] In 2014, Supreme Court notified the Supreme Court Rules, 2013 replacing the 1966 Rules effective from 19 August 2014.[11]

text: Reporting and citation[edit]

text: Supreme Court Reports is the official journal of Reportable Supreme Court Decisions. It is published under the authority of the Supreme Court of India by the Controller of Publications, Government of India, Delhi.[43] In addition, there are many other reputed private journals that report Supreme Court decisions. Some of these other important journals are: SCR (The Supreme Court Reports), SCC(Supreme Court Cases), AIR (All India Reporter), SCALE, etc.

text: Facilities on the campus[edit]

text: Legal-aid,[44][45][46] court-fee vendors, first-aid post, dental clinic, physiotherapy unit and pathology lab; rail-reservation counter, canteen, post office and a branch and 3 ATMs of UCO Bank, Supreme Court Museum[8] can be availed by litigants and visitors.

text: Landmark judgments[edit]

text: Land reform[edit]

text: After some of the courts overturned state laws for redistributing land from zamindar (landlord) estates on the ground that the laws violated the zamindars' fundamental rights, the Parliament passed the 1st amendment to the Constitution in 1951, followed by the 4th amendment in 1955, to uphold its authority to redistribute land. The Supreme Court countered these amendments in 1967 when it ruled in Golaknath v. State of Punjab[47] that the Parliament did not have the power to abrogate fundamental rights, including the provisions on private property. The 25th amendment to the Constitution in 1971 curtailed the right of a citizen to property as a fundamental right and gave authority to the government to infringe private property, which led to a furor amongst the zamindars.

text: Emergency (1975–1977)[edit]

text: The independence of judiciary was severely curtailed[48] during the Indian Emergency (1975–1977) of Indira Gandhi. The constitutional rights of imprisoned persons were restricted under Preventive detention laws passed by the parliament. In the case of Shiva Kant Shukla Additional District Magistrate of Jabalpur v. Shiv Kant Shukla, popularly known as the Habeas Corpus case, a bench of five seniormost judges of Supreme court ruled in favour of state's right for unrestricted powers of detention during the emergency. Justices A.N. Ray, P. N. Bhagwati, Y. V. Chandrachud, and M.H. Beg, stated in the majority decision:[49]

text: The only dissenting opinion was from Justice H. R. Khanna, who stated:

text: It is believed that before delivering his dissenting opinion, Justice Khanna had mentioned to his sister: "I have prepared my judgment, which is going to cost me the Chief Justice-ship of India."[50] In January 1977, Justice Khanna was superseded despite being the most senior judge at the time and thereby Government broke the convention of appointing only the senior most judge to the position of Chief Justice of India. Justice Khanna remains a legendary figure among the legal fraternity in India for this decision.

text: The New York Times, wrote of this opinion: "The submission of an independent judiciary to absolutist government is virtually the last step in the destruction of a democratic society; and the Indian Supreme Court's decision appears close to utter surrender."

text: During the emergency period, the government also passed the 39th amendment, which sought to limit judicial review for the election of the Prime Minister; only a body constituted by Parliament could review this election.[51] Subsequently, the parliament, with most opposition members in jail during the emergency, passed the 42nd Amendment which prevented any court from reviewing any amendment to the constitution with the exception of procedural issues concerning ratification. A few years after the emergency, however, the Supreme court rejected the absoluteness of the 42nd amendment and reaffirmed its power of judicial review in the Minerva Mills case (1980).

text: Post-1980: an assertive court[edit]

text: After Indira Gandhi lost elections in 1977, the new government of Morarji Desai, and especially law minister Shanti Bhushan (who had earlier argued for the detenues in the Habeas Corpus case), introduced a number of amendments making it more difficult to declare and sustain an emergency, and reinstated much of the power to the Supreme Court. It is said that the Basic Structure doctrine, created in Kesavananda Bharati v. State of Kerala, was strengthened in Indira Gandhi's case and set in stone in [Minerva Mills v. Union of India].[52]

text: The Supreme Court's creative and expansive interpretations of Article 21 (Life and Personal Liberty), primarily after the Emergency period, have given rise to a new jurisprudence of public interest litigation that has vigorously promoted many important economic and social rights (constitutionally protected but not enforceable) including, but not restricted to, the rights to free education, livelihood, a clean environment,[53] food and many others. Civil and political rights (traditionally protected in the Fundamental Rights chapter of the Indian Constitution) have also been expanded and more fiercely protected. These new interpretations have opened the avenue for litigation on a number of important issues.

text: Recent important cases[edit]

text: Among the important pronouncements of the Supreme Court post 2000 is the Coelho case I.R. Coelho v. State of Tamil Nadu (Judgment of 11 January 2007). A unanimous Bench of 9 judges reaffirmed the basic structure doctrine. It held that a constitutional amendment which entails violation of any fundamental rights which the Court regards as forming part of the basic structure of the Constitution, then the same can be struck down depending upon its impact and consequences. The judgment clearly imposes further limitations on the constituent power of Parliament with respect to the principles underlying certain fundamental rights. The judgment in Coelho has in effect restored the decision in Golak Nath regarding non-amendability of the Constitution on account of infraction of fundamental rights, contrary to the judgment in the Kesavananda Bharati case.

text: Another important decision was of the five-judge Bench in Ashoka Kumara Thakur v. Union of India; where the constitutional validity of Central Educational Institutions (Reservations in Admissions) Act, 2006 was upheld, subject to the "creamy layer" criteria. Importantly, the Court refused to follow the 'strict scrutiny' standards of review followed by the United States Supreme Court. At the same time, the Court has applied the strict scrutiny standards in Anuj Garg v. Hotel Association of India (2007) ([1])

text: 2G spectrum scam[edit]

text: The Supreme Court declared allotment of spectrum as "unconstitutional and arbitrary" and quashed all the 122 licenses issued in 2008 during tenure of A. Raja (then minister for communications & IT), the main official accused in the 2G scam case.[54]

text: Black money[edit]

text: The government refused to disclose details of about 18 Indians holding accounts in LGT Bank, Liechtenstein, evoking a sharp response from a Bench comprising Justices B Sudershan Reddy and S S Nijjar. The court ordered Special investigation team (SIT) to probe the matter.[55][56] Lack of enthusiasm made the court create a special investigative team (SIT).[57]

text: Minority reservations[edit]

text: The Supreme Court refused to stay the Andhra Pradesh High Court judgement quashing 4.5% sub-quota for minorities under OBC reservation quota of 27%.[58]

text: Online/postal ballot for Indian citizen living abroad (NRIs)[edit]

text: Three judge bench presided by Honorable Chief Justice Altamas Kabir issued notice to the Centre and the Election Commission of India (EC) on the PIL filed by a group of NRIs for online/postal ballot for the Indian citizens living abroad.[59][60]

text: Recognition of transgender as 'third gender' in law[edit]

text: In April 2014, Justice KS Radhakrishnan declared transgender to be the 'third gender' in Indian law, in a case brought by the National Legal Services Authority (Nalsa) against Union of India and others.[61][62][63] The ruling said:[64]

text: Seldom, our society realises or cares to realise the trauma, agony and pain which the members of Transgender community undergo, nor appreciates the innate feelings of the members of the Transgender community, especially of those whose mind and body disown their biological sex. Our society often ridicules and abuses the Transgender community and in public places like railway stations, bus stands, schools, workplaces, malls, theatres, hospitals, they are sidelined and treated as untouchables, forgetting the fact that the moral failure lies in the society's unwillingness to contain or embrace different gender identities and expressions, a mindset which we have to change.

text: Justice Radhakrishnan said that transgender people should be treated consistently with other minorities under the law, enabling them to access jobs, healthcare and education.[65] He framed the issue as one of human rights, saying that, "These TGs, even though insignificant in numbers, are still human beings and therefore they have every right to enjoy their human rights", concluding by declaring that:[64]

text: (1) Hijras, eunuchs, apart from binary gender, be treated as "third gender" for the purpose of safeguarding their rights under Part III of our Constitution and the laws made by the Parliament and the State Legislature.

text: (2) Transgender persons' right to decide their self-identified gender is also upheld and the Centre and State Governments are directed to grant legal recognition of their gender identity such as male, female or as third gender.

text: Relief to over 35,000 public servants[edit]

text: In B.Prabhakara Rao vs. State of A.P. involved sudden reduction in age of superannuation from 58 years to 55 years of over 35,000 public servants of State Government, public sector undertakings, statutory bodies, educational institutions and Tirupathi-Tirumalai Devasthanams (TTD). They lost first round of litigation in the Supreme Court. Realising the mistake, fresh legislation was brought restoring the original age of superannuation of 58 years but providing that the benefit of new legislation would not extend to those whose reduction of age of superannuation had been upheld. In challenge to this law, Subodh Markandeya argued that all that was required was to strike down naughty “not” – which found favour with the Supreme Court bringing relief to over 35,000 public servants.[66][67]

text: Criticism[edit]

text: 2008 saw the Supreme Court embroiled in several controversies, from serious allegations of corruption at the highest level of the judiciary,[68] expensive private holidays at the tax payers expense,[69] refusal to divulge details of judges' assets to the public,[70] secrecy in the appointments of judges',[71] to refusal to make information public under the Right to Information Act.[72] The Chief Justice K. G. Balakrishnan invited a lot of criticism for his comments on his post not being that of a public servant, but that of a constitutional authority.[73] He later went back on this stand.[74] The judiciary has come in for serious criticisms from former Presidents of India Pratibha Patil and A. P. J. Abdul Kalam for failure in handling its duties.[75] Former Prime Minister Manmohan Singh, has stated that corruption is one of the major challenges facing the judiciary, and suggested that there is an urgent need to eradicate this menace.[76]

text: The Cabinet Secretary of the Indian government introduced the Judges Inquiry (Amendment) Bill 2008 in Parliament for setting up of a panel called the National Judicial Council, headed by the Chief Justice of India, that will probe into allegations of corruption and misconduct by High Court and Supreme Court judges.[77][78]

text: According to Supreme Court newsletter, there are 58,519 cases pending in the Supreme Court, out of which 37,385 are pending for more than a year, at the end of 2011. Excluding connected cases, there are still 33,892 pending cases.[79] As per the latest pendency data made available by the Supreme Court, the total number of pending cases in the Supreme Court as on 1 April 2014 is 64,330, which includes 34,144 Admission matters (miscellaneous) and 30,186 Regular Hearing matters.[80] In May, 2014, former Chief Justice of India, Justice R.M. Lodha, proposed to make Indian judiciary work throughout the year (instead of the present system of having long vacations, specially in the higher courts) in order to reduce pendency of cases in Indian courts; however, as per this proposal there is not going to be any increase in the number of working days or working hours of any of the judges and it only meant that different judges would be going on vacation during different periods of the year as per their choice; but, the Bar Council of India rejected this proposal mainly because it would have inconvenienced the advocates who would have to work throughout the year.[81]