|Part of a series on the|
The discovery of the 118 chemical elements known to exist as of 2019 is presented in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesise more elements, and it is not known how many elements are possible.
Each element's name, atomic number, year of first report, name of the discoverer, and notes related to the discovery are listed.
Periodic table by era of discovery
|Z||Element||Earliest use||Oldest |
|Discoverers||Place of |
|29||Copper||9000 BC||6000 BC||Middle East||Anatolia||Copper was probably the first metal mined and crafted by humans. It was originally obtained as a native metal and later from the smelting of ores. Earliest estimates of the discovery of copper suggest around 9000 BC in the Middle East. It was one of the most important materials to humans throughout the Chalcolithic and Bronze Ages. Copper beads dating from 6000 BC have been found in Çatal Höyük, Anatolia and the archaeological site of Belovode on the Rudnik mountain in Serbia contains the world's oldest securely dated evidence of copper smelting from 5000 BC.|
|82||Lead||7000 BC||3800 BC||Africa||Abydos, Egypt||It is believed that lead smelting began at least 9,000 years ago, and the oldest known artifact of lead is a statuette found at the temple of Osiris on the site of Abydos dated around 3800 BC.|
|79||Gold||Before 6000 BC||Before 4000 BC||Levant||Nahal Qana||The earliest gold artifacts were discovered at the site of Nahal Qana in the Levant.|
|47||Silver||Before 5000 BC||ca. 4000 BC||Asia Minor||Asia Minor||Estimated to have been discovered in Asia Minor shortly after copper and gold.|
|26||Iron||Before 5000 BC||4000 BC||Middle East||Egypt||There is evidence that iron was known from before 5000 BC. The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in about 4000 BC. The discovery of smelting around 3000 BC led to the start of the Iron age around 1200 BC and the prominent use of iron for tools and weapons.|
|6||Carbon||3750 BC||2500 BC||Egyptians and Sumerians||Middle East||The earliest known use of charcoal was for the reduction of copper, zinc, and tin ores in the manufacture of bronze, by the Egyptians and Sumerians. Diamonds were probably known as early as 2500 BC. True chemical analyses were made in the 18th century, and in 1789 carbon was listed by Antoine Lavoisier as an element.|
|50||Tin||3500 BC||2000 BC||Asia Minor||Kestel||First smelted in combination with copper around 3500 BC to produce bronze (and thus giving place to the Bronze Age in those places where Iron Age did not intrude directly on Neolithic of the Stone Age).[ clarification needed ] Kestel, in southern Turkey, is the site of an ancient Cassiterite mine that was used from 3250 to 1800 BC. The oldest artifacts date from around 2000 BC.|
|16||Sulfur||Before 2000 BC||Before AD 815||Middle East||Middle East||First used at least 4,000 years ago. According to the Ebers Papyrus, a sulfur ointment was used in ancient Egypt to treat granular eyelids. Recognized as an element by Jabir ibn Hayyan before AD 815, and by Antoine Lavoisier in 1777.|
|80||Mercury||1500 BC||1500 BC||Egyptians||Egypt||Found in Egyptian tombs dating from 1500 BC.|
|30||Zinc||Before 1000 BC||1000 BC||Indian metallurgists||Indian subcontinent||Used as a component of brass since antiquity (before 1000 BC) by Indian metallurgists, but its true nature was not understood in ancient times. Identified as a distinct metal in the Rasaratna Samuccaya around the 14th century of the Christian era and by the alchemist Paracelsus in 1526. Isolated by Andreas Sigismund Marggraf in 1746.|
|33||Arsenic||Before AD 815||Before AD 815||Middle-Eastern alchemists||Middle East||The use of metallic arsenic was described by the Egyptian alchemist Zosimos. The purification of arsenic was later described by Persian alchemist Jabir ibn Hayyan. Albertus Magnus (c. 1200-1280) is typically credited with the description of the metalloid in the West.|
|51||Antimony||Before AD 815||Before AD 815||Jabir ibn Hayyan||Middle East||Dioscorides and Pliny both describe the accidental production of metallic antimony from stibnite, but only seem to recognize the metal as lead. The intentional isolation of antimony is described by Persian alchemist Jabir ibn Hayyan. In Europe, the metal was being produced and used by 1540, when it was described by Vannoccio Biringuccio.|
|83||Bismuth||Before AD 1000||Before AD 1000||Jabirian corpus||Middle East||Described by Persian alchemist Jabir ibn Hayyan in the Jabirian corpus. Later described in Europe by Claude François Geoffroy in 1753.|
|Z||Element||Observed or predicted||Isolated (widely known)||Notes|
|15||Phosphorus||1669||H. Brand||1669||H. Brand||Prepared from urine, it was the first element to be discovered since ancient times.|
|27||Cobalt||1735||G. Brandt||1735||G. Brandt||Proved that the blue color of glass is due to a new kind of metal and not bismuth as thought previously.|
|78||Platinum||1735||A. de Ulloa||First description of a metal found in South American gold was in 1557 by Julius Caesar Scaliger. Ulloa published his findings in 1748, but Sir Charles Wood also investigated the metal in 1741. First reference to it as a new metal was made by William Brownrigg in 1750.|
|28||Nickel||1751||F. Cronstedt||1751||F. Cronstedt||Found by attempting to extract copper from the mineral known as fake copper (now known as niccolite).|
|12||Magnesium||1755||J. Black||1808||H. Davy||Black observed that magnesia alba (MgO) was not quicklime (CaO). Davy isolated the metal electrochemically from magnesia.|
|1||Hydrogen||1766||H. Cavendish||ca. 1500||Paracelsus||Cavendish was the first to distinguish H|
2 from other gases, although Paracelsus around 1500, Robert Boyle, and Joseph Priestley had observed its production by reacting strong acids with metals. Lavoisier named it in 1783. It was the first elemental gas known.
|8||Oxygen||1771||W. Scheele||1604||Sendivogius||Obtained it by heating mercuric oxide and nitrates in 1771, but did not publish his findings until 1777. Joseph Priestley also prepared this new air by 1774, but only Lavoisier recognized it as a true element; he named it in 1777. Before him, Sendivogius had produced oxygen by heating saltpetre, correctly identifying it as the "food of life".|
|7||Nitrogen||1772||D. Rutherford||1772||D. Rutherford||He discovered nitrogen while he was studying at the University of Edinburgh. He showed that the air in which animals had breathed, even after removal of the exhaled carbon dioxide, was no longer able to burn a candle. Carl Wilhelm Scheele, Henry Cavendish, and Joseph Priestley also studied the element at about the same time, and Lavoisier named it in 1775-6.|
|56||Barium||1772||W. Scheele||1808||H. Davy||Scheele distinguished a new earth (BaO) in pyrolusite and Davy isolated the metal by electrolysis.|
|17||Chlorine||1774||W. Scheele||1774||W. Scheele||Obtained it from hydrochloric acid, but thought it was an oxide. Only in 1808 did Humphry Davy recognize it as an element.|
|25||Manganese||1774||W. Scheele||1774||G. Gahn||Distinguished pyrolusite as the calx of a new metal. Ignatius Gottfred Kaim also discovered the new metal in 1770, as did Scheele in 1774. It was isolated by reduction of manganese dioxide with carbon.|
|42||Molybdenum||1778||W. Scheele||1781||J. Hjelm||Scheele recognised the metal as a constituent of molybdena.|
|74||Tungsten||1781||W. Scheele||1783||J. and F. Elhuyar||Scheele obtained from scheelite an oxide of a new element. The Elhuyars obtained tungstic acid from wolframite and reduced it with charcoal.|
|52||Tellurium||1782||F.-J.M. von Reichenstein||H. Klaproth||Muller observed it as an impurity in gold ores from Transylvania.|
|38||Strontium||1787||W. Cruikshank||1808||H. Davy||Cruikshank and Adair Crawford in 1790 concluded that strontianite contained a new earth. It was eventually isolated electrochemically in 1808 by Humphry Davy.|
|1789||A. Lavoisier||The first modern list of chemical elements – containing 33 elements including light, heat, unextracted "radicals" and some oxides. He also redefined the term "element". Until then, no metals except mercury were considered elements.|
|40||Zirconium||1789||H. Klaproth||1824||J. Berzelius||Martin Heinrich Klaproth identified a new element in zirconia.|
|92||Uranium||1789||H. Klaproth||1841||E.-M. Péligot||Klaproth mistakenly identified a uranium oxide obtained from pitchblende as the element itself and named it after the recently discovered planet Uranus.|
|22||Titanium||1791||W. Gregor||1825||J. Berzelius||Gregor found an oxide of a new metal in ilmenite; Klaproth independently discovered the element in rutile in 1795 and named it. The pure metallic form was only obtained in 1910 by Matthew A. Hunter.|
|39||Yttrium||1794||J. Gadolin||1843||H. Rose||Discovered in gadolinite, but Mosander showed later that its ore, yttria, contained more elements. Wöhler mistakenly thought he had isolated the metal in 1828 from a volatile chloride he supposed to be yttrium chloride, but Rose proved otherwise in 1843 and correctly isolated the element himself that year.|
|24||Chromium||1794||N. Vauquelin||1797||N. Vauquelin||Vauquelin discovered the trioxide in crocoite ore, and later isolated the metal by heating the oxide in a charcoal oven.|
|4||Beryllium||1798||N. Vauquelin||1828||F. Wöhler and A. Bussy||Vauquelin discovered the oxide in beryl and emerald, and Klaproth suggested the present name around 1808.|
|23||Vanadium||1801||M. del Río||1830||N.G.Sefström||Río found the metal in vanadinite but retracted the claim after Hippolyte Victor Collet-Descotils disputed it. Sefström isolated and named it, and later it was shown that Río had been right in the first place.|
|41||Niobium||1801||C. Hatchett||1864||W. Blomstrand||Hatchett found the element in columbite ore and named it columbium. Heinrich Rose proved in 1844 that the element is distinct from tantalum, and renamed it niobium which was officially accepted in 1949.|
|73||Tantalum||1802||G. Ekeberg||Ekeberg found another element in minerals similar to columbite and in 1844, Heinrich Rose proved that it was distinct from niobium.|
|46||Palladium||1802||W. H. Wollaston||1802||W. H. Wollaston||Wollaston discovered it in samples of platinum from South America, but did not publish his results immediately. He had intended to name it after the newly discovered asteroid, Ceres, but by the time he published his results in 1804, cerium had taken that name. Wollaston named it after the more recently discovered asteroid Pallas.|
|58||Cerium||1803||H. Klaproth, J. Berzelius, and W. Hisinger||1838||G. Mosander||Berzelius and Hisinger discovered the element in ceria and named it after the newly discovered asteroid (then considered a planet), Ceres. Klaproth discovered it simultaneously and independently in some tantalum samples. Mosander proved later that the samples of all three researchers had at least another element in them, lanthanum.|
|76||Osmium||1803||S. Tennant||1803||S. Tennant||Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium.|
|77||Iridium||1803||S. Tennant||1803||S. Tennant||Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium, and published the iridium results in 1804.|
|45||Rhodium||1804||H. Wollaston||1804||H. Wollaston||Wollaston discovered and isolated it from crude platinum samples from South America.|
|19||Potassium||1807||H. Davy||1807||H. Davy||Davy discovered it by using electrolysis on potash.|
|11||Sodium||1807||H. Davy||1807||H. Davy||Andreas Sigismund Marggraf recognised the difference between soda ash and potash in 1758. Davy discovered sodium a few days after potassium, by using electrolysis on sodium hydroxide.|
|20||Calcium||1808||H. Davy||1808||H. Davy||Davy discovered the metal by electrolysis of quicklime.|
|5||Boron||1808||L. Gay-Lussac and L.J. Thénard||1808||H. Davy||Radical boracique appears on the list of elements in Lavoisier's Traité Élémentaire de Chimie from 1789. On June 21, 1808, Lussac and Thénard announced a new element in sedative salt, Davy announced the isolation of a new substance from boracic acid on June 30.|
|9||Fluorine||1810||A.-M. Ampère||1886||H. Moissan||Radical fluorique appears on the list of elements in Lavoisier's Traité Élémentaire de Chimie from 1789, but radical muriatique also appears instead of chlorine. André-Marie Ampère predicted an element analogous to chlorine obtainable from hydrofluoric acid, and between 1812 and 1886 many researchers tried to obtain this element. It was eventually isolated by Moissan.|
|53||Iodine||1811||B. Courtois||1811||B. Courtois||Courtois discovered it in the ashes of seaweed.|
|3||Lithium||1817||A. Arfwedson||1821||W. T. Brande||Arfwedson discovered the alkali in petalite.|
|48||Cadmium||1817||S. L Hermann, F. Stromeyer, and J.C.H. Roloff||1817||S. L Hermann, F. Stromeyer, and J.C.H. Roloff||All three found an unknown metal in a sample of zinc oxide from Silesia, but the name that Stromeyer gave became the accepted one.|
|34||Selenium||1817||J. Berzelius and G. Gahn||1817||J. Berzelius and G. Gahn||While working with lead they discovered a substance that they thought was tellurium, but realized after more investigation that it was different.|
|14||Silicon||1823||J. Berzelius||1823||J. Berzelius||Humphry Davy thought in 1800 that silica was a compound, not an element, and in 1808 suggested the present name. In 1811 Louis-Joseph Gay-Lussac and Louis-Jacques Thénard probably prepared impure silicon, but Berzelius is credited with the discovery for obtaining the pure element in 1823.|
|13||Aluminium||1825||H.C.Ørsted||1825||H.C.Ørsted||Antoine Lavoisier predicted in 1787 that alumina is the oxide of an undiscovered element, and in 1808 Humphry Davy tried to decompose it. Although he failed, he suggested the present name. Hans Christian Ørsted was the first to isolate metallic aluminium in 1825.|
|35||Bromine||1825||J. Balard and C. Löwig||1825||J. Balard and C. Löwig||They both discovered the element in the autumn of 1825. Balard published his results the next year, but Löwig did not publish until 1827.|
|90||Thorium||1829||J. Berzelius||1914||D. Lely, Jr. and L. Hamburger||Berzelius obtained the oxide of a new earth in thorite.|
|57||Lanthanum||1838||G. Mosander||1841||G. Mosander||Mosander found a new element in samples of ceria and published his results in 1842, but later he showed that this lanthana contained four more elements.|
|68||Erbium||1843||G. Mosander||1879||T. Cleve||Mosander managed to split the old yttria into yttria proper and erbia, and later terbia too.|
|65||Terbium||1843||G. Mosander||1886||J.C.G. de Marignac||Mosander managed to split the old yttria into yttria proper and erbia, and later terbia too.|
|44||Ruthenium||1844||K. Claus||1844||K. Claus||Gottfried Wilhelm Osann thought that he found three new metals in Russian platinum samples, and in 1844 Karl Karlovich Klaus confirmed that there was a new element.|
|55||Caesium||1860||R. Bunsen and R. Kirchhoff||1882||C. Setterberg||Bunsen and Kirchhoff were the first to suggest finding new elements by spectrum analysis. They discovered caesium by its two blue emission lines in a sample of Dürkheim mineral water. The pure metal was eventually isolated in 1882 by Setterberg.|
|37||Rubidium||1861||R. Bunsen and G. R. Kirchhoff||Hevesy||Bunsen and Kirchhoff discovered it just a few months after caesium, by observing new spectral lines in the mineral lepidolite. Bunsen never obtained a pure sample of the metal, which was later obtained by Hevesy.|
|81||Thallium||1861||W. Crookes||1862||C.-A. Lamy||Shortly after the discovery of rubidium, Crookes found a new green line in a selenium sample; later that year, Lamy found the element to be metallic.|
|49||Indium||1863||F. Reich and T. Richter||1867||T. Richter||Reich and Richter First identified it in sphalerite by its bright indigo-blue spectroscopic emission line. Richter isolated the metal several years later.|
|2||Helium||1868||P. Janssen and N. Lockyer||1895||W. Ramsay, T. Cleve, and N. Langlet||Janssen and Lockyer observed independently a yellow line in the solar spectrum that did not match any other element. This was the first observation of a noble gas, located in the Sun. Years later after the isolation of argon on Earth, Ramsay, Cleve, and Langlet observed independently helium trapped in cleveite.|
|1869||D. I. Mendeleev||Mendeleev arranges the 64 elements known at that time into the first modern periodic table and correctly predicts several others.|
|31||Gallium||1875||P. E. L. de Boisbaudran||P. E. L. de Boisbaudran||Boisbaudran observed on a pyrenea blende sample some emission lines corresponding to the eka-aluminium that was predicted by Mendeleev in 1871 and subsequently isolated the element by electrolysis.|
|70||Ytterbium||1878||J.C.G. de Marignac||1906||C. A. von Welsbach||On October 22, 1878, Marignac reported splitting terbia into two new earths, terbia proper and ytterbia.|
|67||Holmium||1878||J.-L. Soret and M. Delafontaine||1879||T. Cleve||Soret found it in samarskite and later, Per Teodor Cleve split Marignac's erbia into erbia proper and two new elements, thulium and holmium. Delafontaine's philippium turned out to be identical to what Soret found.|
|69||Thulium||1879||T. Cleve||1879||T. Cleve||Cleve split Marignac's erbia into erbia proper and two new elements, thulium and holmium.|
|21||Scandium||1879||F. Nilson||1879||F. Nilson||Nilson split Marignac's ytterbia into pure ytterbia and a new element that matched Mendeleev's 1871 predicted eka-boron.|
|62||Samarium||1879||P.E.L. de Boisbaudran||1879||P.E.L. de Boisbaudran||Boisbaudran noted a new earth in samarskite and named it samaria after the mineral.|
|64||Gadolinium||1880||J. C. G. de Marignac||1886||P.E.L. de Boisbaudran||Marignac initially observed the new earth in terbia, and later Boisbaudran obtained a pure sample from samarskite.|
|59||Praseodymium||1885||C. A. von Welsbach||Carl Auer von Welsbach discovered two new distinct elements in Mosander's didymia: praseodymium and neodymium.|
|60||Neodymium||1885||C. A. von Welsbach||Carl Auer von Welsbach discovered two new distinct elements in Mosander's didymia: praseodymium and neodymium.|
|32||Germanium||1886||C. A. Winkler||In February 1886 Winkler found in argyrodite the eka-silicon that Mendeleev had predicted in 1871.|
|66||Dysprosium||1886||P.E.L. de Boisbaudran||De Boisbaudran found a new earth in erbia.|
|18||Argon||1894||Lord Rayleigh and W. Ramsay||1894||Lord Rayleigh and W. Ramsay||They discovered the gas by comparing the molecular weights of nitrogen prepared by liquefaction from air and nitrogen prepared by chemical means. It is the first noble gas to be isolated.|
|63||Europium||1896||E.-A. Demarçay||1901||E.-A. Demarçay||Demarçay found spectral lines of a new element in Lecoq's samarium, and separated this element several years later.|
|36||Krypton||1898||W. Ramsay and W. Travers||1898||W. Ramsay and W. Travers||On May 30, 1898, Ramsay separated a noble gas from liquid argon by difference in boiling point.|
|10||Neon||1898||W. Ramsay and W. Travers||1898||W. Ramsay and W. Travers||In June 1898 Ramsay separated a new noble gas from liquid argon by difference in boiling point.|
|54||Xenon||1898||W. Ramsay and W. Travers||1898||W. Ramsay and W. Travers||On July 12, 1898 Ramsay separated a third noble gas within three weeks, from liquid argon by difference in boiling point.|
|84||Polonium||1898||P. and M. Curie||1902||W. Marckwald||In an experiment done on July 13, 1898, the Curies noted an increased radioactivity in the uranium obtained from pitchblende, which they ascribed to an unknown element.|
|88||Radium||1898||P. and M. Curie||1902||M. Curie||The Curies reported on December 26, 1898, a new element different from polonium, which Marie later isolated from uraninite.|
|86||Radon||1899||E. Rutherford and R. B. Owens||1910||W. Ramsay and R. Whytlaw-Gray||Rutherford and Owens discovered a radioactive gas resulting from the radioactive decay of thorium, isolated later by Ramsay and Gray. In 1900, Friedrich Ernst Dorn discovered a longer-lived isotope of the same gas from the radioactive decay of radium. Since "radon" was first used to specifically designate Dorn's isotope before it became the name for the element, he is often mistakenly given credit for the latter instead of the former.|
|89||Actinium||1902||F. O. Giesel||1902||F. O. Giesel||Giesel obtained from pitchblende a substance that had properties similar to those of lanthanum and named it emanium. André-Louis Debierne had previously reported the discovery of a new element actinium that was supposedly similar to titanium and thorium; the elements were mistakenly identified as being identical and Debierne's name was chosen, even though in retrospect Debierne's substance could not have included much actual element 89.|
|71||Lutetium||1906||C. A. von Welsbach and G. Urbain||1906||C. A. von Welsbach||von Welsbach proved that the old ytterbium also contained a new element, which he named cassiopeium. Urbain also proved this simultaneously, but his samples were very impure and only contained trace quantities of the new element. Despite this, his chosen name lutetium was adopted.|
|75||Rhenium||1908||M. Ogawa||1919||M. Ogawa||Ogawa found it in thorianite but assigned it as element 43 instead of 75 and named it nipponium. In 1925 Walter Noddack, Ida Eva Tacke and Otto Berg announced its separation from gadolinite and gave it the present name.|
|91||Protactinium||1913||O. H. Göhring and K. Fajans||1927||A. von Grosse||The two obtained the first isotope of this element that had been predicted by Mendeleev in 1871 as a member of the natural decay of 238U. Originally isolated in 1900 by William Crookes, who nevertheless did not recognize that it was a new element.|
|72||Hafnium||1922||D. Coster and G. von Hevesy||1922||D. Coster and G. von Hevesy||Georges Urbain claimed to have found the element in rare-earth residues, while Vladimir Vernadsky independently found it in orthite. Neither claim was confirmed due to World War I, and neither could be confirmed later, as the chemistry they reported does not match that now known for hafnium. After the war, Coster and Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon. Hafnium was the last stable element to be discovered.|
|43||Technetium||1937||C. Perrier and E. Segrè||1937||C. Perrier & E.Segrè||The two discovered a new element in a molybdenum sample that was used in a cyclotron, the first synthetic element to be discovered, though it was later found out that it does occur naturally in minuscule trace quantities. It had been predicted by Mendeleev in 1871 as eka-manganese.|
|87||Francium||1939||M. Perey||Perey discovered it as a decay product of 227Ac. Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well.|
|93||Neptunium||1940||E.M. McMillan and H. Abelson||Obtained by irradiating uranium with neutrons, it is the first transuranium element discovered.|
|85||Astatine||1940||R. Corson, R. MacKenzie and E. Segrè||Obtained by bombarding bismuth with alpha particles. Later determined to occur naturally in minuscule quantities (<25 grams in earth's crust).|
|94||Plutonium||1940–1941||Glenn T. Seaborg, Arthur C. Wahl, W. Kennedy and E.M. McMillan||Prepared by bombardment of uranium with deuterons.|
|61||Promethium||1942||S. Wu, E.G. Segrè and H. Bethe||1945||Charles D. Coryell, Jacob A. Marinsky, Lawrence E. Glendenin, and Harold G. Richter [ citation needed ]||It was probably first prepared in 1942 by bombarding neodymium and praseodymium with neutrons, but separation of the element could not be carried out. Isolation was performed under the Manhattan Project in 1945.|
|96||Curium||1944||Glenn T. Seaborg, Ralph A. James and Albert Ghiorso||Prepared by bombarding plutonium with alpha particles during the Manhattan Project|
|95||Americium||1944||G. T. Seaborg, R. A. James, O. Morgan and A. Ghiorso||Prepared by irradiating plutonium with neutrons during the Manhattan Project.|
|97||Berkelium||1949||G. Thompson, A. Ghiorso and G. T. Seaborg (University of California, Berkeley)||Created by bombardment of americium with alpha particles.|
|98||Californium||1950||S. G. Thompson, K. Street, Jr., A. Ghiorso and G. T. Seaborg (University of California, Berkeley)||Bombardment of curium with alpha particles.|
|99||Einsteinium||1952||A. Ghiorso et al. (Argonne Laboratory, Los Alamos Laboratory and University of California, Berkeley)||1952||Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons; kept secret for several years.|
|100||Fermium||1952||A. Ghiorso et al. (Argonne Laboratory, Los Alamos Laboratory and University of California, Berkeley)||Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons; kept secret for several years.|
|101||Mendelevium||1955||A. Ghiorso, G. Harvey, R. Choppin, S. G. Thompson and G. T. Seaborg (Berkeley Radiation Laboratory)||Prepared by bombardment of einsteinium with helium.|
|103||Lawrencium||1961||A. Ghiorso, T. Sikkeland, E. Larsh and M. Latimer (Berkeley Radiation Laboratory)||First prepared by bombardment of californium with boron atoms.|
|102||Nobelium||1966||E. D. Donets, V. A. Shchegolev and V. A. Ermakov (JINR in Dubna)||First prepared by bombardment of uranium with neon atoms|
|104||Rutherfordium||1969||A. Ghiorso et al. (Berkeley Radiation Laboratory) and I. Zvara et al. (JINR in Dubna)||Prepared by bombardment of californium with carbon atoms by Albert Ghiorso's team and by bombardment of plutonium with neon atoms by Zvara's team.|
|105||Dubnium||1970||A. Ghiorso et al. (Berkeley Radiation Laboratory) and V. A. Druin et al. (JINR in Dubna)||Prepared by bombardment of californium with nitrogen atoms by Ghiorso's team and by bombardment of americium with neon atoms by Druin's team.|
|106||Seaborgium||1974||A. Ghiorso et al. (Berkeley Radiation Laboratory)||Prepared by bombardment of californium with oxygen atoms.|
|107||Bohrium||1981||G.Münzenberg et al. (GSI in Darmstadt)||Obtained by bombarding bismuth with chromium.|
|109||Meitnerium||1982||G. Münzenberg, P. Armbruster et al. (GSI in Darmstadt)||Prepared by bombardment of bismuth with iron atoms.|
|108||Hassium||1984||G. Münzenberg, P. Armbruster et al. (GSI in Darmstadt)||Prepared by bombardment of lead with iron atoms|
|110||Darmstadtium||1994||S. Hofmann et al. (GSI in Darmstadt)||Prepared by bombardment of lead with nickel|
|111||Roentgenium||1994||S. Hofmann et al. (GSI in Darmstadt)||Prepared by bombardment of bismuth with nickel|
|112||Copernicium||1996||S. Hofmann et al. (GSI in Darmstadt)||Prepared by bombardment of lead with zinc.|
|114||Flerovium||1999||Y. Oganessian et al. (JINR in Dubna)||Prepared by bombardment of plutonium with calcium|
|116||Livermorium||2000||Y. Oganessian et al. (JINR in Dubna)||Prepared by bombardment of curium with calcium|
|118||Oganesson||2002||Y. Oganessian et al. (JINR in Dubna)||Prepared by bombardment of californium with calcium|
|115||Moscovium||2003||Y. Oganessian et al. (JINR in Dubna)||Prepared by bombardment of americium with calcium|
|113||Nihonium||2003–2004||Y. Oganessian et al. (JINR in Dubna) and K. Morita et al. (RIKEN in Wako, Japan)||Prepared by decay of moscovium by Oganessian's team and bombardment of bismuth with zinc by Morita's team|
|117||Tennessine||2009||Y. Oganessian et al. (JINR in Dubna)||Prepared by bombardment of berkelium with calcium|
Rutherfordium is a synthetic chemical element with the symbol Rf and atomic number 104, named after New Zealand physicist Ernest Rutherford. As a synthetic element, it is not found in nature and can only be created in a laboratory. It is radioactive; the most stable known isotope, 267Rf, has a half-life of approximately 1.3 hours.
Seaborgium is a synthetic chemical element with the symbol Sg and atomic number 106. It is named after the American nuclear chemist Glenn T. Seaborg. As a synthetic element, it can be created in a laboratory but is not found in nature. It is also radioactive; the most stable known isotope, 269Sg, has a half-life of approximately 14 minutes.
Darmstadtium is a chemical element with the symbol Ds and atomic number 110. It is an extremely radioactive synthetic element. The most stable known isotope, darmstadtium-281, has a half-life of approximately 12.7 seconds. Darmstadtium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near the city of Darmstadt, Germany, after which it was named.
Livermorium is a synthetic chemical element with the symbol Lv and has an atomic number of 116. It is an extremely radioactive element that has only been created in the laboratory and has not been observed in nature. The element is named after the Lawrence Livermore National Laboratory in the United States, which collaborated with the Joint Institute for Nuclear Research (JINR) in Dubna, Russia to discover livermorium during experiments made between 2000 and 2006. The name of the laboratory refers to the city of Livermore, California where it is located, which in turn was named after the rancher and landowner Robert Livermore. The name was adopted by IUPAC on May 30, 2012. Four isotopes of livermorium are known, with mass numbers between 290 and 293 inclusive; the longest-lived among them is livermorium-293 with a half-life of about 60 milliseconds. A fifth possible isotope with mass number 294 has been reported but not yet confirmed.
Oganesson is a synthetic chemical element with the symbol Og and atomic number 118. It was first synthesized in 2002 at the Joint Institute for Nuclear Research (JINR) in Dubna, near Moscow, Russia, by a joint team of Russian and American scientists. In December 2015, it was recognized as one of four new elements by the Joint Working Party of the international scientific bodies IUPAC and IUPAP. It was formally named on 28 November 2016. The name is in line with the tradition of honoring a scientist, in this case the nuclear physicist Yuri Oganessian, who has played a leading role in the discovery of the heaviest elements in the periodic table. It is one of only two elements named after a person who was alive at the time of naming, the other being seaborgium, and the only element whose namesake is alive today.
Moscovium is a synthetic chemical element with the symbol Mc and atomic number 115. It was first synthesized in 2003 by a joint team of Russian and American scientists at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. In December 2015, it was recognized as one of four new elements by the Joint Working Party of international scientific bodies IUPAC and IUPAP. On 28 November 2016, it was officially named after the Moscow Oblast, in which the JINR is situated.
Copernicium is a synthetic chemical element with the symbol Cn and atomic number 112. Its known isotopes are extremely radioactive, and have only been created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of approximately 28 seconds. Copernicium was first created in 1996 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the astronomer Nicolaus Copernicus.
Flerovium is a superheavy artificial chemical element with the symbol Fl and atomic number 114. It is an extremely radioactive synthetic element. The element is named after the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research in Dubna, Russia, where the element was discovered in 1998. The name of the laboratory, in turn, honours the Russian physicist Georgy Flyorov. The name was adopted by IUPAC on 30 May 2012.
Nihonium is a synthetic chemical element with the symbol Nh and atomic number 113. It is extremely radioactive; its most stable known isotope, nihonium-286, has a half-life of about 10 seconds. In the periodic table, nihonium is a transactinide element in the p-block. It is a member of period 7 and group 13.
The year 2004 in science and technology involved some significant events.
Rutherfordium (104Rf) is a synthetic element and thus has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was either 259Rf in 1966 or 257Rf in 1969. There are 16 known radioisotopes from 253Rf to 270Rf and 4 isomers. The longest-lived isotope is 267Rf with a half-life of 2.5 hours, and the longest-lived isomer is 261mRf with a half-life of 81 seconds.
Seaborgium (106Sg) is a synthetic element and so has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was 263mSg in 1974. There are 12 known radioisotopes from 258Sg to 271Sg and 2 known isomers. The longest-lived isotope is 269Sg with a half-life of 14 minutes.
Hassium (108Hs) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 265Hs in 1984. There are 12 known isotopes from 263Hs to 277Hs and 1–4 isomers. The longest-lived isotope is 269Hs with a half-life of 16 seconds.
Darmstadtium (110Ds) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 269Ds in 1994. There are 9 known radioisotopes from 267Ds to 281Ds and 2 or 3 known isomers. The longest-lived isotope is 281Ds with a half-life of 9.6 seconds.
Copernicium (112Cn) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 277Cn in 1996. There are 6 known radioisotopes ; the longest-lived isotope is 285Cn with a half-life of 29 seconds.
Nihonium (113Nh) is a synthetic element. Being synthetic, a standard atomic weight cannot be given and like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 284Nh as a decay product of 288Mc in 2003. The first isotope to be directly synthesized was 278Nh in 2004. There are 6 known radioisotopes from 278Nh to 286Nh, along with the unconfirmed 287Nh and 290Nh. The longest-lived isotope is 286Nh with a half-life of 8 seconds.
Flerovium (114Fl) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 289Fl in 1999. Flerovium has seven known isotopes, and possibly 2 nuclear isomers. The longest-lived isotope is 289Fl with a half-life of 1.9 seconds, but the unconfirmed 290Fl may have a longer half-life of 19 seconds.
Livermorium (116Lv) is an artificial element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 293Lv in 2000. There are four known radioisotopes from 290Lv to 293Lv, as well as a few suggestive indications of a possible heavier isotope 294Lv. The longest-lived of the four well-characterised isotopes is 293Lv with a half-life of 53 ms.
Oganesson (118Og) is a synthetic element created in particle accelerators, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 294Og in 2002 and 2005; it has a half-life of 0.7 milliseconds. An unconfirmed isotope, 295Og, may have been observed in 2011 with a longer half-life of 181 milliseconds.
Yuri Tsolakovich Oganessian is a Russian-Armenian nuclear physicist who is considered the world's leading researcher in superheavy chemical elements. He led the discovery of these elements in the periodic table. He succeeded Georgy Flyorov as director of the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research in 1989 and is now its scientific leader. The heaviest element on the periodic table, oganesson, is named after him, only the second time that an element was named after a living scientist.
Probably metallic antimony was being produced in Germany in Biringuccio's time, for later in this chapter he mentions importation of cakes of the smelted (or melted) metal to alloy with pewter or bell metal.
...today's inclination to re-evaluate the work of Delafontaine and Soret has led justifiably to their being included as co-discoverers of holmium.