The discovery of the elements known to exist today is presented here 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 defined.

Given is each element's name, atomic number

Atomic number

In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element...

, year of first report, name of the discoverer, and some notes related to the discovery.

Unrecorded discoveries

Z Atomic number In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element...	Name	Earliest use	Oldest existing sample	Discoverers	Place of oldest sample	Notes
29	Copper Copper Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...	9000 BC	6000 BC	Middle East	Anatolia	Copper was probably the first metal mined and crafted by man. 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 copper Copper Age The Chalcolithic |stone]]") period or Copper Age, also known as the Eneolithic/Æneolithic , is a phase of the Bronze Age in which the addition of tin to copper to form bronze during smelting remained yet unknown by the metallurgists of the times...  and bronze age Bronze Age The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age... s. Copper beads dating from 6000 BC have been found in Çatal Höyük, Anatolia Anatolia Anatolia is a geographic and historical term denoting the westernmost protrusion of Asia, comprising the majority of the Republic of Turkey... .
79	Gold Gold Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...	before 6000 BC	5500 BC	Middle East	Egypt Egypt Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...	Archaeologists suggest that the first use of gold began with the first civilizations in the Middle East. It may have been the first metal used by humans. The oldest remaining gold jewelry is that in the tomb of Egyptian Queen Zer.
82	Lead Lead Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...	7000 BC	3800 BC	Near East	Abydos, Egypt Abydos, Egypt Abydos is one of the most ancient cities of Upper Egypt, and also of the eight Upper Nome, of which it was the capital city. It is located about 11 kilometres west of the Nile at latitude 26° 10' N, near the modern Egyptian towns of el-'Araba el Madfuna and al-Balyana...	It is believed that lead smelting began at least 9000 years ago, and the oldest known artifact of lead is a statuette found at the temple of Osiris Osiris Osiris is an Egyptian god, usually identified as the god of the afterlife, the underworld and the dead. He is classically depicted as a green-skinned man with a pharaoh's beard, partially mummy-wrapped at the legs, wearing a distinctive crown with two large ostrich feathers at either side, and...  on the site of Abydos dated circa 3800 BC.
47	Silver Silver Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...	before 5000 BC	~4000 BC	?	Asia Minor	Estimated to have been discovered shortly after copper and gold.
26	Iron Iron Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...	before 5000 BC	4000 BC	? History of ferrous metallurgy The history of ferrous metallurgy began far back in prehistory. The earliest surviving iron artifacts, from the 5th millennium BC in Iran and 2nd millennium BC in China, were made from meteoritic iron-nickel. It is not known when or where the smelting of iron from ores began, but by the end of the...	Egypt Egypt Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...	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 Iron Age The Iron Age is the archaeological period generally occurring after the Bronze Age, marked by the prevalent use of iron. The early period of the age is characterized by the widespread use of iron or steel. The adoption of such material coincided with other changes in society, including differing...  around 1200 BC and the prominent use of iron for tools and weapons.
6	Carbon Carbon Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...	3750 BC	?	Egyptians and Sumerians	?	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. Diamond Diamond In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions... s were probably known as early as 2500 BC. The first true chemical analyses were made in the 18th century, and in 1789 carbon was listed by Antoine Lavoisier Antoine Lavoisier Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...  as an element.
50	Tin Tin Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...	3500 BC	2000 BC	?	?	First smelted in combination with copper around 3500 BC to produce bronze Bronze Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...  and brass Brass Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin... . The oldest artifacts date from around 2000 BC.
16	Sulfur Sulfur Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...	before 2000 BC	?	Chinese/Indians	?	First used at least 4000 years ago. Recognized as an element by Antoine Lavoisier Antoine Lavoisier Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...  in 1777.
80	Mercury Mercury (element) Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...	before 2000 BC	1500 BC	Chinese/Indians	Egypt Egypt Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...	Known to ancient Chinese and Indians before 2000 BC, and found in Egyptian tombs dating from 1500 BC.
30	Zinc Zinc Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...	before 1000 BC	1000 BC	Indian metallurgists	Indian subcontinent Indian subcontinent The Indian subcontinent, also Indian Subcontinent, Indo-Pak Subcontinent or South Asian Subcontinent is a region of the Asian continent on the Indian tectonic plate from the Hindu Kush or Hindu Koh, Himalayas and including the Kuen Lun and Karakoram ranges, forming a land mass which extends...	Extracted as a metal since antiquity (before 1000 BC) by Indian metallurgists, but the true nature of this metal was not understood in ancient times. Identified as a unique metal by the metallurgist Rasaratna Samuccaya in 800 and by the alchemist Paracelsus Paracelsus Paracelsus was a German-Swiss Renaissance physician, botanist, alchemist, astrologer, and general occultist....  in 1526. Isolated by Andreas Sigismund Marggraf Andreas Sigismund Marggraf Andreas Sigismund Marggraf was a German chemist and pioneer of analytical chemistry from Berlin, which was then the capital of Brandenburg, a major principality of the Holy Roman Empire. He isolated zinc in 1746 by heating calamine and carbon...  in 1746.
33	Arsenic Arsenic Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...	2500 BC/1250 AD	bronze age	A.Magnus Albertus Magnus Albertus Magnus, O.P. , also known as Albert the Great and Albert of Cologne, is a Catholic saint. He was a German Dominican friar and a bishop, who achieved fame for his comprehensive knowledge of and advocacy for the peaceful coexistence of science and religion. Those such as James A. Weisheipl...		In use in the early bronze age; Albertus Magnus Albertus Magnus Albertus Magnus, O.P. , also known as Albert the Great and Albert of Cologne, is a Catholic saint. He was a German Dominican friar and a bishop, who achieved fame for his comprehensive knowledge of and advocacy for the peaceful coexistence of science and religion. Those such as James A. Weisheipl...  was the first European to isolate the element in 1250. In 1649, Johann Schröder Johann Schröder Johann Schröder was a German physician and pharmacologist who was the first person to recognise that arsenic was an element. In 1649, he produced the elemental form of arsenic by heating its oxide, and published two methods for its preparation.-References:...  published two ways of preparing elemental arsenic.
51	Antimony Antimony Antimony is a toxic chemical element with the symbol Sb and an atomic number of 51. A lustrous grey metalloid, it is found in nature mainly as the sulfide mineral stibnite...	3000 BC				In widespread use in Egypt and the Middle East. Basilius Valentinus Basilius Valentinus Basil Valentine is the Anglicised version of the name Basilius Valentinus, who was allegedly a 15th-century alchemist. There are claims that he was the Canon of the Benedictine Priory of Sankt Peter in Erfurt, Germany but according to John Maxson Stillman, who wrote on the history of chemistry,...  was the first European to describe the element around 1450. First description of a procedure for isolating elemental antimony in 1540 was by Vannoccio Biringuccio Vannoccio Biringuccio - External links :*... .
24	Chromium Chromium Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...	before 0	before 0	Terracotta Army Terracotta Army The Terracotta Army or the "Terra Cotta Warriors and Horses", is a collection of terracotta sculptures depicting the armies of Qin Shi Huang, the first Emperor of China...	China	Found coating various weapons in China because of its high strength and corrosion resistance.
83	Bismuth Bismuth Bismuth is a chemical element with symbol Bi and atomic number 83. Bismuth, a trivalent poor metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally uncombined, although its sulfide and oxide form important commercial ores. The free element is 86% as dense as lead...	1753		C.F.Geoffroy Claude François Geoffroy Claude François Geoffroy was a French chemist. He discovered the chemical element bismuth in 1753. Before this time, bismuth-containing minerals were frequently identified as either lead or tin ores....		Described in writings attributed to Basilius Valentinus Basilius Valentinus Basil Valentine is the Anglicised version of the name Basilius Valentinus, who was allegedly a 15th-century alchemist. There are claims that he was the Canon of the Benedictine Priory of Sankt Peter in Erfurt, Germany but according to John Maxson Stillman, who wrote on the history of chemistry,...  around 1450. Definitively identified by Claude François Geoffroy Claude François Geoffroy Claude François Geoffroy was a French chemist. He discovered the chemical element bismuth in 1753. Before this time, bismuth-containing minerals were frequently identified as either lead or tin ores....  in 1753.

Recorded discoveries

Z	Element name	Observed or predicted	Isolation (widely known)	Observer	First isolator	Notes
15	Phosphorus Phosphorus Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...	1669	1669	H.Brand Hennig Brand Hennig Brand was a merchant and alchemist in Hamburg, Germany. He discovered phosphorus around 1669.-Early life:The circumstances of Brand's birth are unknown. Some sources describe his origins as humble and indicate that he had been an apprentice glass-maker as a young man...	H.Brand	Prepared from urine, it was the first element to be chemically discovered.
27	Cobalt Cobalt Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....	1732	?	G.Brandt Georg Brandt -External links:** by Uno Boklund in: Charles C. Gillispie, ed., Dictionary of Scientific Biography , vol. 2, pages 421-422....	?	Proved that the blue color of glass is due to a new kind of metal and not bismuth as thought previously.
78	Platinum Platinum Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...	1735	1735	A.de Ulloa Antonio de Ulloa Antonio de Ulloa y de la Torre-Girault was a Spanish general, explorer, author, astronomer, colonial administrator and the first Spanish governor of Louisiana.Rebellion of 1768]]....	A. de Ulloa	First description of a metal found in South America South America South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east... n gold was in 1557 by Julius Caesar Scaliger Julius Caesar Scaliger Julius Caesar Scaliger was an Italian scholar and physician who spent a major part of his career in France. He employed the techniques and discoveries of Renaissance humanism to defend Aristotelianism against the new learning... . 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 William Brownrigg William Brownrigg M.D. F.R.S. was a doctor and scientist, who practised at Whitehaven in Cumberland. While there, William Brownrigg carried out experiments that won him not only a place in The Royal Society but the prized Copley Medal....  in 1750.
28	Nickel Nickel Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...	1751	1751	A.F.Cronstedt Axel Fredrik Cronstedt Baron Axel Fredrik Cronstedt was a Swedish mineralogist and chemist who discovered nickel in 1751 as a mining expert with the Bureau of Mines. Cronstedt described it as kupfernickel...	A.F.Cronstedt	Found by attempting to extract copper from the mineral known as "fake copper" (now known as niccolite Niccolite Nickeline or niccolite is a mineral consisting of nickel arsenide, NiAs, containing 43.9% nickel and 56.1% arsenic.Small quantities of sulfur, iron and cobalt are usually present, and sometimes the arsenic is largely replaced by antimony... ).
12	Magnesium Magnesium Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...	1755	1808	J.Black Joseph Black Joseph Black FRSE FRCPE FPSG was a Scottish physician and chemist, known for his discoveries of latent heat, specific heat, and carbon dioxide. He was professor of Medicine at University of Glasgow . James Watt, who was appointed as philosophical instrument maker at the same university...	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	Black observed that magnesia alba (MgO) was not quicklime (CaO). Davy isolated the metal electrochemically from magnesia.
1	Hydrogen Hydrogen Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...	1766	1500	H.Cavendish Henry Cavendish Henry Cavendish FRS was a British scientist noted for his discovery of hydrogen or what he called "inflammable air". He described the density of inflammable air, which formed water on combustion, in a 1766 paper "On Factitious Airs". Antoine Lavoisier later reproduced Cavendish's experiment and...	Paracelsus Paracelsus Paracelsus was a German-Swiss Renaissance physician, botanist, alchemist, astrologer, and general occultist....	Cavendish was the first to distinguish from other gases, although Paracelsus Paracelsus Paracelsus was a German-Swiss Renaissance physician, botanist, alchemist, astrologer, and general occultist....  around 1500, Robert Boyle, and Joseph Priestley had observed its production by reacting strong acids with metals. Lavoisier named it in 1793.
8	Oxygen Oxygen Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...	1771	1771	C.W.Scheele Carl Wilhelm Scheele Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist. Isaac Asimov called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit...	C.W.Scheele	Obtained it by heating mercuric oxide and nitrate Nitrate The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a... s in 1771, but did not publish his findings until 1777. Joseph Priestley Joseph Priestley Joseph Priestley, FRS was an 18th-century English theologian, Dissenting clergyman, natural philosopher, chemist, educator, and political theorist who published over 150 works...  also prepared this new air by 1774, but only Lavoisier recognized it as a true element; he named it in 1777.
7	Nitrogen Nitrogen Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...	1772	1772	D.Rutherford Daniel Rutherford Daniel Rutherford was a Scottish physician, chemist and botanist who is most famous for the isolation of nitrogen in 1772.Rutherford was the uncle of the novelist Sir Walter Scott.-Early life:...	D.Rutherford	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 Carl Wilhelm Scheele Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist. Isaac Asimov called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit... , Henry Cavendish Henry Cavendish Henry Cavendish FRS was a British scientist noted for his discovery of hydrogen or what he called "inflammable air". He described the density of inflammable air, which formed water on combustion, in a 1766 paper "On Factitious Airs". Antoine Lavoisier later reproduced Cavendish's experiment and... , and Joseph Priestley Joseph Priestley Joseph Priestley, FRS was an 18th-century English theologian, Dissenting clergyman, natural philosopher, chemist, educator, and political theorist who published over 150 works...  also studied the element at about the same time, and Lavoisier named it in 1775-6.
17	Chlorine Chlorine Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...	1774	1774	C.W.Scheele Carl Wilhelm Scheele Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist. Isaac Asimov called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit...	C.W.Scheele	Obtained it from hydrochloric acid Hydrochloric acid Hydrochloric acid is a solution of hydrogen chloride in water, that is a highly corrosive, strong mineral acid with many industrial uses. It is found naturally in gastric acid.... , but thought it was an oxide. Only in 1808 did Humphry Davy recognize it as an element.
25	Manganese Manganese Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...	1770	1774	T.O.Bergman	J.G.Gahn Johan Gottlieb Gahn Johan Gottlieb Gahn was a Swedish chemist and metallurgist who discovered manganese in 1774.Gahn studied in Uppsala 1762-1770 and became acquainted with chemists Torbern Bergman och Carl Wilhelm Scheele...	Distinguished pyrolusite Pyrolusite Pyrolusite is a mineral consisting essentially of manganese dioxide and is important as an ore of manganese. It is a black, amorphous appearing mineral, often with a granular, fibrous or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black...  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.
56	Barium Barium Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...	1772	1808	C.W.Scheele Carl Wilhelm Scheele Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist. Isaac Asimov called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit...	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	Scheele distinguished a new earth (BaO BAO BAO may refer to:* Baccalaureus in Arte Obstetricia, Bachelor of Obstetrics, a medical degree unique to Ireland.* Baryon acoustic oscillations, a signature of the early universe observed in galaxy surveys.* Benny Anderssons Orkester* Bullets And Octane... ) in pyrolusite Pyrolusite Pyrolusite is a mineral consisting essentially of manganese dioxide and is important as an ore of manganese. It is a black, amorphous appearing mineral, often with a granular, fibrous or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black...  and Davy isolated the metal by electrolysis Electrolysis In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction... .
42	Molybdenum Molybdenum Molybdenum , is a Group 6 chemical element with the symbol Mo and atomic number 42. The name is from Neo-Latin Molybdaenum, from Ancient Greek , meaning lead, itself proposed as a loanword from Anatolian Luvian and Lydian languages, since its ores were confused with lead ores...	1778	1781	C.W.Scheele Carl Wilhelm Scheele Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist. Isaac Asimov called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit...	P.J.Hjelm	Scheele recognised the metal as a constituent of molybdena Molybdenite Molybdenite is a mineral of molybdenum disulfide, MoS2. Similar in appearance and feel to graphite, molybdenite has a lubricating effect that is a consequence of its layered structure. The atomic structure consists of a sheet of molybdenum atoms sandwiched between sheets of sulfur atoms... .
52	Tellurium	1782	1795?	F.-J.M. von Reichenstein Franz-Joseph Müller von Reichenstein Franz-Joseph Müller Freiherr von Reichenstein or Franz-Joseph Müller von Reichenstein was an Austrian mineralogist and mining engineer. Müller held several positions in the Austria-Hungarian administration of mines and coinage in the Banat, Transylvania, and Tyrol...	M.H.Klaproth Martin Heinrich Klaproth Martin Heinrich Klaproth was a German chemist.Klaproth was born in Wernigerode. During a large portion of his life he followed the profession of an apothecary...	Muller observed it as an impurity in gold ores from Transylvania.
74	Tungsten Tungsten Tungsten , also known as wolfram , is a chemical element with the chemical symbol W and atomic number 74.A hard, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth only in chemical compounds. It was identified as a new element in 1781, and first isolated as...	1781	1783	T.Bergman Torbern Bergman Torbern Olof Bergman was a Swedish chemist and mineralogist noted for his 1775 Dissertation on Elective Attractions, containing the largest chemical affinity tables ever published...	J.J.Elhuyar Juan José Elhuyar Juan José Elhuyar Lubize was a Spanish chemist and mineralogist, the joint discoverer of tungsten with his brother Fausto Elhuyar in 1783.... , &F.Elhuyar Fausto Elhuyar Fausto de Elhuyar was a Spanish chemist, and the joint discoverer of tungsten with his brother Juan José Elhuyar in 1783. Fausto de Elhuyar was in charge, under a King of Spain commission, of organizing the School of Mines in México City and so was responsible of building an architectural jewel...	Bergman obtained from scheelite Scheelite Scheelite is a calcium tungstate mineral with the chemical formula CaWO4. It is an important ore of tungsten. Well-formed crystals are sought by collectors and are occasionally fashioned into gemstones when suitably free of flaws...  an oxide of a new element. The Elhuyars obtained tungstic acid Tungstic acid Tungstic acid refers to hydrated forms of tungsten trioxide, WO3.The simplest form, the monohydrate, is WO3.H2O, the dihydrate WO3.2H2O is also known. The solid state structure of WO3.H2O consists of layers of octahedrally coordinated WO5 units where 4 vertices are shared. the dihydrate has the...  from wolframite Wolframite Wolframite WO4, is an iron manganese tungstate mineral that is the intermediate between ferberite and huebernite . Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite is found in quartz veins and pegmatites associated with granitic intrusives...  and reduced it with charcoal.
38	Strontium Strontium Strontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and...	1787	1808	W.Cruikshank William Cruickshank (chemist) William Cruickshank was a Scottish military surgeon and chemist, and professor of chemistry at the Royal Military Academy, Woolwich.-Career:...	H.Davy	Cruikshank and Adair Crawford Adair Crawford Adair Crawford FRS , a chemist and physician, was a pioneer in the development of calorimetric methods for measuring the specific heat capacity of substances and the heat of chemical reactions...  in 1790 concluded that strontianite Strontianite Strontianite is an important raw material for the extraction of strontium. It is a rare carbonate mineral and one of only a few strontium minerals...  contained a new earth. It was eventually isolated electrochemically in 1808 by Humphry Davy.
		1789		A.Lavoisier Antoine Lavoisier Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...		The first modern list of chemical elements - containing, among others, 23 elements of those known then. He also redefined the term "element". Until him, all metals except mercury were not considered elements.
40	Zirconium Zirconium Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium...	1789	1824	M.H.Klaproth Martin Heinrich Klaproth Martin Heinrich Klaproth was a German chemist.Klaproth was born in Wernigerode. During a large portion of his life he followed the profession of an apothecary...	J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...	Klaproth identified a new element in zirconia.
92	Uranium Uranium Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...	1789	1841	M.H.Klaproth Martin Heinrich Klaproth Martin Heinrich Klaproth was a German chemist.Klaproth was born in Wernigerode. During a large portion of his life he followed the profession of an apothecary...	E.-M.Péligot Eugène-Melchior Péligot Eugène-Melchior Péligot , also known as Eugène Péligot, was a French chemist who isolated the first sample of uranium metal in 1841....	Mistakenly identified a uranium oxide Uranium oxide Uranium oxide is an oxide of the element uranium.The metal uranium forms several oxides:* Uranium dioxide or uranium oxide * Uranium trioxide or uranium oxide...  obtained from pitchblende as the element itself and named it after the recently discovered planet Uranus Uranus Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus , the father of Cronus and grandfather of Zeus... .
22	Titanium Titanium Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....	1791	1825	W.Gregor William Gregor William Gregor was the British clergyman and mineralogist who discovered the elemental metal titanium.-Early years:...	J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...	Gregor found an oxide of a new metal in ilmenite Ilmenite Ilmenite is a weakly magnetic titanium-iron oxide mineral which is iron-black or steel-gray. It is a crystalline iron titanium oxide . It crystallizes in the trigonal system, and it has the same crystal structure as corundum and hematite.... ; Martin Heinrich Klaproth Martin Heinrich Klaproth Martin Heinrich Klaproth was a German chemist.Klaproth was born in Wernigerode. During a large portion of his life he followed the profession of an apothecary...  independently discovered the element in rutile Rutile Rutile is a mineral composed primarily of titanium dioxide, TiO2.Rutile is the most common natural form of TiO2. Two rarer polymorphs of TiO2 are known:...  in 1795 and named it. The pure metallic form was only obtained in 1910 by Matthew A. Hunter.
39	Yttrium Yttrium Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element". Yttrium is almost always found combined with the lanthanides in rare earth minerals and is...	1794	1840	J.Gadolin Johan Gadolin Johan Gadolin was a Finnish chemist, physicist and mineralogist. Gadolin discovered the chemical element yttrium...	C.G.Mosander	Discovered in gadolinite Gadolinite Gadolinite, sometimes also known as Ytterbite, is a silicate mineral which consists principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron with the formula 2FeBe2Si2O10... , but Mosander showed later that its ore, yttria, contained more elements.
4	Beryllium Beryllium Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...	1798	1828	L.N.Vauquelin Louis Nicolas Vauquelin Nicolas Louis Vauquelin , was a French pharmacist and chemist.-Early life:Vauquelin was born at Saint-André-d'Hébertot in Normandy, France. His first acquaintance with chemistry was gained as laboratory assistant to an apothecary in Rouen , and after various vicissitudes he obtained an introduction...	F.Wöhler Friedrich Wöhler Friedrich Wöhler was a German chemist, best known for his synthesis of urea, but also the first to isolate several chemical elements.-Biography:He was born in Eschersheim, which belonged to aau... &A.Bussy Antoine Bussy Antoine Alexandre Brutus Bussy was a French chemist who primarily studied bussays.Antoine Bussy entered the Ecole Polytechnique in 1813, and there followed the courses delivered by Pierre Robiquet, the great French chemist who was to make decisive breakthroughs in bio-chemistry Antoine Alexandre...	Vauquelin discovered the oxide in beryl Beryl The mineral beryl is a beryllium aluminium cyclosilicate with the chemical formula Be3Al26. The hexagonal crystals of beryl may be very small or range to several meters in size. Terminated crystals are relatively rare...  and emerald, and Klaproth suggested the present name around 1808.
23	Vanadium Vanadium Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature...	1801	1830	A.M.del Río Andrés Manuel del Río Andrés Manuel del Río Fernández was a Spanish–Mexican scientist and naturalist who discovered the chemical element vanadium.-Education:...	N.G.Sefström Nils Gabriel Sefström Nils Gabriel Sefström was a Swedish chemist. Sefström was a student of Berzelius and, when studying the brittleness of steel in 1830, he rediscovered a new chemical element, to which he gave the name vanadium....	Río found the metal in vanadinite Vanadinite Vanadinite is a mineral belonging to the apatite group of phosphates, with the chemical formula Pb53Cl. It is one of the main industrial ores of the metal vanadium and a minor source of lead. A dense, brittle mineral, it is usually found in the form of red hexagonal crystals. It is an uncommon...  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 Niobium Niobium or columbium , is a chemical element with the symbol Nb and atomic number 41. It's a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite...	1801	1864	C.Hatchett Charles Hatchett Charles Hatchett FRS was an English chemist who discovered the element niobium.- Biography:Hatchett was born, raised, and lived in London...	C.W.Blomstrand Christian Wilhelm Blomstrand Christian Wilhelm Blomstrand was a Swedish mineralogist and chemist.Blomstrand was born in Växjö, Sweden and studied chemistry at the University of Lund, where he received his Ph.D in 1850 and his habilitation in 1854. After a expedition to Spitsbergen and a being a lecturer at the Elementary...	Hatchett found the element in columbite Columbite Columbite, also called niobite, niobite-tantalite and columbate [2O6], is a black mineral group that is an ore of niobium and tantalum. It has a submetallic luster and a high density and is a niobate of iron and manganese, containing tantalate of iron. This mineral group was first found in Haddam,...  ore and named it columbium. Heinrich Rose Heinrich Rose Heinrich Rose was a German mineralogist and analytical chemist. He was the brother of the mineralogist Gustav Rose and a son of Valentin Rose....  proved in 1844 that the element is distinct from tantalum, and renamed it niobium which was officially accepted in 1949.
73	Tantalum Tantalum Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as tantalium, the name comes from Tantalus, a character in Greek mythology. Tantalum is a rare, hard, blue-gray, lustrous transition metal that is highly corrosion resistant. It is part of the refractory...	1802	?	A.G.Ekeberg Anders Gustaf Ekeberg Anders Gustaf Ekeberg was a Swedish chemist who discovered tantalum in 1802. He was notably deaf...	?	Ekeberg found another element in minerals similar to columbite Columbite Columbite, also called niobite, niobite-tantalite and columbate [2O6], is a black mineral group that is an ore of niobium and tantalum. It has a submetallic luster and a high density and is a niobate of iron and manganese, containing tantalate of iron. This mineral group was first found in Haddam,...  and in 1844, Heinrich Rose proved that it was distinct from niobium.
46	Palladium Palladium Palladium is a chemical element with the chemical symbol Pd and an atomic number of 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired...	1803	1803	W.H.Wollaston William Hyde Wollaston William Hyde Wollaston FRS was an English chemist and physicist who is famous for discovering two chemical elements and for developing a way to process platinum ore.-Biography:...	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 Asteroid Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones... , 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 2 Pallas Pallas, formally designated 2 Pallas, is the second asteroid to have been discovered , and one of the largest. It is estimated to constitute 7% of the mass of the asteroid belt, and its diameter of 530–565 km is comparable to, or slightly larger than, that of 4 Vesta. It is however 20%... .
58	Cerium Cerium Cerium is a chemical element with the symbol Ce and atomic number 58. It is a soft, silvery, ductile metal which easily oxidizes in air. Cerium was named after the dwarf planet . Cerium is the most abundant of the rare earth elements, making up about 0.0046% of the Earth's crust by weight...	1803	1839	M.H.Klaproth Martin Heinrich Klaproth Martin Heinrich Klaproth was a German chemist.Klaproth was born in Wernigerode. During a large portion of his life he followed the profession of an apothecary... , J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...  & W.Hisinger Wilhelm Hisinger Wilhelm Hisinger was a Swedish physicist and chemist who in 1807, working in coordination with Jöns Jakob Berzelius, noted that in electrolysis any given substance always went to the same pole, and that substances attracted to the same pole had other properties in common...	C.G.Mosander Carl Gustaf Mosander Carl Gustaf Mosander was a Swedish chemist. He discovered the elements lanthanum, erbium and terbium....	Berzelius and Hisinger discovered the element in ceria and named it after the newly discovered asteroid Asteroid Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...  (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 Lanthanum Lanthanum is a chemical element with the symbol La and atomic number 57.Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series. It is found in some rare-earth minerals, usually in combination with cerium and... .
76	Osmium Osmium Osmium is a chemical element with the symbol Os and atomic number 76. Osmium is a hard, brittle, blue-gray or blue-blacktransition metal in the platinum family, and is the densest natural element. Osmium is twice as dense as lead. The density of osmium is , slightly greater than that of iridium,...	1803	1803	S.Tennant Smithson Tennant Smithson Tennant FRS was an English chemist.Tennant is best known for his discovery of the elements iridium and osmium, which he found in the residues from the solution of platinum ores in 1803. He also contributed to the proof of the identity of diamond and charcoal. The mineral tennantite is...	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 Iridium Iridium is the chemical element with atomic number 77, and is represented by the symbol Ir. A very hard, brittle, silvery-white transition metal of the platinum family, iridium is the second-densest element and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C...	1803	1803	S.Tennant Smithson Tennant Smithson Tennant FRS was an English chemist.Tennant is best known for his discovery of the elements iridium and osmium, which he found in the residues from the solution of platinum ores in 1803. He also contributed to the proof of the identity of diamond and charcoal. The mineral tennantite is...	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 Rhodium Rhodium is a chemical element that is a rare, silvery-white, hard and chemically inert transition metal and a member of the platinum group. It has the chemical symbol Rh and atomic number 45. It is composed of only one isotope, 103Rh. Naturally occurring rhodium is found as the free metal, alloyed...	1804	1804	W.H.Wollaston William Hyde Wollaston William Hyde Wollaston FRS was an English chemist and physicist who is famous for discovering two chemical elements and for developing a way to process platinum ore.-Biography:...	W.H.Wollaston	Wollaston discovered and isolated it from crude platinum samples from South America.
19	Potassium Potassium Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...	1807	1807	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	H.Davy	Davy discovered it by using electrolysis Electrolysis In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...  on potash Potash Potash is the common name for various mined and manufactured salts that contain potassium in water-soluble form. In some rare cases, potash can be formed with traces of organic materials such as plant remains, and this was the major historical source for it before the industrial era... .
11	Sodium Sodium Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...	1807	1807	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	H.Davy	Davy discovered it a few days after potassium, by using electrolysis Electrolysis In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...  on sodium hydroxide.
20	Calcium Calcium Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...	1808	1808	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	H.Davy	Davy discovered the metal by electrolysis Electrolysis In chemistry and manufacturing, electrolysis is a method of using a direct electric current to drive an otherwise non-spontaneous chemical reaction...  of quicklime.
5	Boron Boron Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...	1808	1808	J.L.Gay-Lussac Joseph Louis Gay-Lussac - External links :* from the American Chemical Society* from the Encyclopædia Britannica, 10th Edition * , Paris...  & L.J.Thénard Louis Jacques Thénard Louis Jacques Thénard , was a French chemist.His father, a poor peasant, managed to have him educated at the academy of Sens, and sent him at the age of sixteen to study pharmacy in Paris. There he attended the lectures of Antoine François Fourcroy and Louis Nicolas Vauquelin...	H.Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...	On June 30, 1808, Lussac and Thénard announced a new element in sedative salt Boric acid Boric acid, also called hydrogen borate or boracic acid or orthoboric acid or acidum boricum, is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a... , and nine days later Davy announced the isolation of metallic boron.
53	Iodine Iodine Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....	1811	1811	B.Courtois Bernard Courtois Bernard Courtois, also spelled Barnard Courtois, was a French chemist born in Dijon, France.- Early life :...	B.Courtois	Courtois discovered it in the ashes of sea weed.
3	Lithium Lithium Lithium is a soft, silver-white metal that belongs to the alkali metal group of chemical elements. It is represented by the symbol Li, and it has the atomic number 3. Under standard conditions it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly...	1817	1817	J.A.Arfwedson Johan August Arfwedson Johan August Arfwedson was a Swedish chemist who discovered the chemical element lithium in 1817 by isolating it as a salt.- Life and work :...	J.A.Arfwedson	Arfwedson discovered the alkali in petalite Petalite Petalite, also known as castorite, is a lithium aluminium tectosilicate mineral LiAlSi4O10, crystallizing in the monoclinic system. Petalite is a member of the feldspathoid group. It occurs as colorless, grey, yellow, yellow grey, to white tabular crystals and columnar masses. Occurs in... .
48	Cadmium Cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...	1817	1817	K.S.L Hermann Karl Samuel Leberecht Hermann Karl Samuel Leberecht Hermann was a German chemist who independently discovered cadmium in 1817.Cadmium was discovered in 1817 by a physician, Friedrich Stromeyer . The element was first found in the condensation of vapors that rose out of a furnace in which zinc oxide was being roasted... , F.Stromeyer& J.C.H. Roloff	K.S.L Hermann, F. Stromeyer, J.C.H. Roloff	All three found an unknown metal in a sample of zinc oxide Zinc oxide Zinc oxide is an inorganic compound with the formula ZnO. It is a white powder that is insoluble in water. The powder is widely used as an additive into numerous materials and products including plastics, ceramics, glass, cement, rubber , lubricants, paints, ointments, adhesives, sealants,...  from Silesia, but the name that Stromeyer gave became the accepted one.
34	Selenium Selenium Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...	1817	1817	J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...  & J.G.Gahn	J.J.Berzelius & J.G.Gahn	While working with lead they discovered a substance that they thought was tellurium, but realized after more investigation that it is different.
14	Silicon Silicon Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...	1824	1824	J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...	J.J.Berzelius	Humphry Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...  thought in 1800 that silica was an element, not a compound, 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 1824.
13	Aluminium Aluminium Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....	1825	1825	H.C.Ørsted Hans Christian Ørsted Hans Christian Ørsted was a Danish physicist and chemist who discovered that electric currents create magnetic fields, an important aspect of electromagnetism...	H.C.Ørsted	Antoine Lavoisier Antoine Lavoisier Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...  predicted in 1787 that alumine Aluminé Aluminé is a second class municipality and the capital city of Aluminé Department located in Neuquén Province, Argentina.-History:Aluminé was established in 1915, due to the departamental reorganization of the Neuquén Territory, today the Neuquén Province....  is the oxide of an undiscovered element, and in 1808 Humphry Davy Humphry Davy Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...  tried to decompose it. Although he failed, he suggested the present name. Hans Christian Ørsted Hans Christian Ørsted Hans Christian Ørsted was a Danish physicist and chemist who discovered that electric currents create magnetic fields, an important aspect of electromagnetism...  was the first to isolate metallic aluminum in 1825.
35	Bromine Bromine Bromine ") is a chemical element with the symbol Br, an atomic number of 35, and an atomic mass of 79.904. It is in the halogen element group. The element was isolated independently by two chemists, Carl Jacob Löwig and Antoine Jerome Balard, in 1825–1826...	1825	1825	A.J.Balard Antoine Jérôme Balard -External links:* , PasteurBrewing.com... , L.Gmelin Leopold Gmelin Leopold Gmelin was a German chemist.Gmelin was the son of Johann Friedrich Gmelin. He studied medicine and chemistry at Göttingen, Tübingen and Vienna, and in 1813 began to lecture on chemistry at Heidelberg, where in 1814 he was appointed extraordinary-, and in 1817 ordinary-, professor of...	A.J.Balard & L.Gmelin	They both discovered the element in the autumn of 1825 and published the results the next year.
90	Thorium Thorium Thorium is a natural radioactive chemical element with the symbol Th and atomic number 90. It was discovered in 1828 and named after Thor, the Norse god of thunder....	1829	?	J.J.Berzelius Jöns Jakob Berzelius Jöns Jacob Berzelius was a Swedish chemist. He worked out the modern technique of chemical formula notation, and is together with John Dalton, Antoine Lavoisier, and Robert Boyle considered a father of modern chemistry...	?	Berzelius obtained the oxide of a new earth in thorite Thorite Thorite, SiO4, is a rare nesosilicate of thorium that crystallizes in the tetragonal system and is isomorphous with zircon and hafnon. It is the most common mineral of thorium and is nearly always strongly radioactive. It was named in 1829 to reflect its thorium content... .
57	Lanthanum Lanthanum Lanthanum is a chemical element with the symbol La and atomic number 57.Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series. It is found in some rare-earth minerals, usually in combination with cerium and...	1838	?	C.G.Mosander Carl Gustaf Mosander Carl Gustaf Mosander was a Swedish chemist. He discovered the elements lanthanum, erbium and terbium....	?	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 Erbium Erbium is a chemical element in the lanthanide series, with the symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth...	1842	?	C.G.Mosander Carl Gustaf Mosander Carl Gustaf Mosander was a Swedish chemist. He discovered the elements lanthanum, erbium and terbium....	?	Mosander managed to split the old yttria into yttria proper and erbia, and later terbia too.
65	Terbium Terbium Terbium is a chemical element with the symbol Tb and atomic number 65. It is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife...	1842	1842	C.G.Mosander Carl Gustaf Mosander Carl Gustaf Mosander was a Swedish chemist. He discovered the elements lanthanum, erbium and terbium....	C.G.Mosander	In 1842 Mosander split yttria into two more earths, erbia and terbia
44	Ruthenium Ruthenium Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most chemicals. The Russian scientist Karl Ernst Claus discovered the element...	1807	1844	J.Sniadecki Jedrzej Sniadecki Jędrzej Śniadecki was a Polish writer, physician, chemist and biologist. His achievements include the creation of modern Polish terminology in the field of chemistry.-Life and work:...	J.Sniadecki	Sniadecki isolated the element in 1807, but his work was not ratified. 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. Klaus is usually recognized as the discoverer of the element.
55	Caesium Caesium Caesium or cesium is the chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28 °C , which makes it one of only five elemental metals that are liquid at room temperature...	1860	1882	R.W.Bunsen Robert Bunsen Robert Wilhelm Eberhard Bunsen was a German chemist. He investigated emission spectra of heated elements, and discovered caesium and rubidium with Gustav Kirchhoff. Bunsen developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organoarsenic...  & G.R.Kirchhoff Gustav Kirchhoff Gustav Robert Kirchhoff was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects...	C.Setterberg	Bunsen and Kirchhoff were the first to suggest finding new elements by spectrum analysis Spectrum analysis Spectrum, also known as emission spectrochemical analysis, is the original scientific method of charting and analyzing the chemical properties of matter and gases by looking at the bands in their optical spectrum... . They discovered caesium by its two blue emission lines in a sample of Dürkheim mineral water Mineral water Mineral water is water containing minerals or other dissolved substances that alter its taste or give it therapeutic value, generally obtained from a naturally occurring mineral spring or source. Dissolved substances in the water may include various salts and sulfur compounds... . The pure metal was eventually isolated in 1882 by Setterberg.
37	Rubidium Rubidium Rubidium is a chemical element with the symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group. Its atomic mass is 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other elements in group 1, such as very rapid...	1861	?	R.W.Bunsen Robert Bunsen Robert Wilhelm Eberhard Bunsen was a German chemist. He investigated emission spectra of heated elements, and discovered caesium and rubidium with Gustav Kirchhoff. Bunsen developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organoarsenic...  & G.R.Kirchhoff Gustav Kirchhoff Gustav Robert Kirchhoff was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects...	Robert Bunsen Robert Bunsen Robert Wilhelm Eberhard Bunsen was a German chemist. He investigated emission spectra of heated elements, and discovered caesium and rubidium with Gustav Kirchhoff. Bunsen developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organoarsenic...	Bunsen and Kirchhoff discovered it just a few months after caesium, by observing new spectral lines in the mineral lepidolite Lepidolite Lepidolite Lepidolite Lepidolite (KLi2Al(Al,Si)3O10(F,OH)2 is a lilac-gray or rose-colored phyllosilicate mineral of the mica group that is a secondary source of lithium. It is associated with other lithium-bearing minerals like spodumene in pegmatite bodies. It is one of the major sources of the... . Bunsen never obtained a pure sample of the metal, which was later obtained by Hervesy.
81	Thallium Thallium Thallium is a chemical element with the symbol Tl and atomic number 81. This soft gray poor metal resembles tin but discolors when exposed to air. The two chemists William Crookes and Claude-Auguste Lamy discovered thallium independently in 1861 by the newly developed method of flame spectroscopy...	1861	1862	W.Crookes William Crookes Sir William Crookes, OM, FRS was a British chemist and physicist who attended the Royal College of Chemistry, London, and worked on spectroscopy...	C.-A.Lamy Claude-Auguste Lamy Claude Auguste Lamy was a French chemist who discovered the element thallium independently from William Crookes in 1862.-Life:...	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 Indium Indium is a chemical element with the symbol In and atomic number 49. This rare, very soft, malleable and easily fusible post-transition metal is chemically similar to gallium and thallium, and shows the intermediate properties between these two...	1863	1867	F.Reich Ferdinand Reich Ferdinand Reich was a German chemist who co-discovered indium in 1863 with Hieronymous Theodor Richter....  & H.T.Richter Hieronymous Theodor Richter Hieronymus Theodor Richter was a German chemist.He was born in Dresden. In 1863, while working at the Freiberg University of Mining and Technology, he co-discovered indium with Ferdinand Reich. In 1875, he became the director of the school. He died 25 September 1898, in Freiberg, Saxony, at the...	T.Richter	Reich and Richter First identified it in sphalerite Sphalerite Sphalerite is a mineral that is the chief ore of zinc. It consists largely of zinc sulfide in crystalline form but almost always contains variable iron. When iron content is high it is an opaque black variety, marmatite. It is usually found in association with galena, pyrite, and other sulfides...  by its bright indigo-blue spectroscopic emission line. Richter isolated the metal several years later.
2	Helium Helium Helium is the chemical element with atomic number 2 and an atomic weight of 4.002602, which is represented by the symbol He. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table...	1868	1895	P.Janssen & J.N.Lockyer Joseph Norman Lockyer Sir Joseph Norman Lockyer, FRS , known simply as Norman Lockyer, was an English scientist and astronomer. Along with the French scientist Pierre Janssen he is credited with discovering the gas helium...	W.Ramsay, P.T.Cleve& N.Langlet	Janssen and Lockyer observed independently a yellow line in the solar spectrum that did not match any other element. Years later, Ramsay, Cleve, and Langlet observed independently the element trapped in cleveite Cleveite Cleveite is a radioactive mineral containing uranium and found in Norway. It is an impure variety of uraninite, and has the composition UO2 with about 10% of the uranium substituted by rare earth elements...  about the same time.
		1869		D.I.Mendeleev Dmitri Mendeleev Dmitri Ivanovich Mendeleev , was a Russian chemist and inventor. He is credited as being the creator of the first version of the periodic table of elements...		Mendeleev arranges the 63 elements known at that time into the first modern periodic table and correctly predicts several others.
31	Gallium Gallium Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies...	1875	?	P.E.L.de Boisbaudran Paul Emile Lecoq de Boisbaudran Paul Émile Lecoq de Boisbaudran was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium.-Biography:...	P.E.L.de Boisbaudran	Boisbaudran observed on a pyrenea blende Blende Blende may refer to:* Sphalerite , the most common usage* Hornblende* Pitchblende* an alternative name for Rana Niejta...  sample some emission lines corresponding to the eka-aluminum that was predicted Mendeleev's predicted elements Professor Dmitri Mendeleev published the first Periodic Table of the Atomic Elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest....  by Mendeleev in 1871 and subsequently isolated the element by electrolysis.
70	Ytterbium Ytterbium Ytterbium is a chemical element with the symbol Yb and atomic number 70. A soft silvery metallic element, ytterbium is a rare earth element of the lanthanide series and is found in the minerals gadolinite, monazite, and xenotime. The element is sometimes associated with yttrium or other related...	1878	?	J.C.G. de Marignac Jean Charles Galissard de Marignac Jean Charles Galissard de Marignac was a Swiss chemist whose work with atomic weights suggested the possibility of isotopes and the packing fraction of nuclei and whose study of the rare earth elements led to his discovery of ytterbium in 1878 and codiscovery of gadolinium in 1880.- Life and work...	?	On October 22, 1878, Marignac reported splitting terbia into two new earths, terbia proper and ytterbia.
67	Holmium Holmium Holmium is a chemical element with the symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Its oxide was first isolated from rare earth ores in 1878 and the element was named after the city of Stockholm....	1878	?	M.Delafontaine Marc Delafontaine Marc Delafontaine was a Swiss chemist who in 1878, along with Jacques-Louis Soret, first observed holmium spectroscopically. In 1879, Per Teodor Cleve chemically separated it from thulium and erbium. The three are given credit for the element's discovery....	?	Delafontaine found it in samarskite Samarskite Samarskite is a radioactive rare earth mineral series which includessamarskite- with formula: 22O8and samarskite- with formula 22O8 The formula for smarskite- is also given as: O4...  and next year, Per Teodor Cleve split Marignac's erbia into erbia proper and two new elements, thulium and holmium.
69	Thulium Thulium Thulium is a chemical element that has the symbol Tm and atomic number 69. Thulium is the second least abundant of the lanthanides . It is an easily workable metal with a bright silvery-gray luster...	1879	1879	P.T.Cleve Per Teodor Cleve Per Teodor Cleve was a Swedish chemist and geologist.After graduating from the Stockholm Gymnasium in 1858, Cleve matriculated at Uppsala University in May 1858, where he received his PhD in 1863...	P.T.Cleve	Cleve split Marignac's erbia into erbia proper and two new elements, thulium and holmium.
21	Scandium Scandium Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic transition metal, it has historically been sometimes classified as a rare earth element, together with yttrium and the lanthanoids...	1879	1879	L.F.Nilson Lars Fredrik Nilson Lars Fredrik Nilson was a Swedish chemist who discovered scandium in 1879.Nilson was born in Skönberga parish in Östergötland, Sweden. His father, Nikolaus, was a farmer. The family moved to Gotland when Lars Fredrik was young. After graduating from school, Lars Fredrik enrolled at Uppsala...	L.F.Nilson	Nilson split Marignac's ytterbia into pure ytterbia and a new element that matched 1871 Mendeleev's predicted Mendeleev's predicted elements Professor Dmitri Mendeleev published the first Periodic Table of the Atomic Elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest....  eka-boron.
62	Samarium Samarium Samarium is a chemical element with the symbol Sm, atomic number 62 and atomic weight 150.36. It is a moderately hard silvery metal which readily oxidizes in air. Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3...	1879	1879	P.E.L. de Boisbaudran Paul Emile Lecoq de Boisbaudran Paul Émile Lecoq de Boisbaudran was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium.-Biography:...	P.E.L. de Boisbaudran	Boisbaudran noted a new earth in samarskite Samarskite Samarskite is a radioactive rare earth mineral series which includessamarskite- with formula: 22O8and samarskite- with formula 22O8 The formula for smarskite- is also given as: O4...  and named it samaria after the mineral.
64	Gadolinium Gadolinium Gadolinium is a chemical element with the symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. It is found in nature only in combined form. Gadolinium was first detected spectroscopically in 1880 by de Marignac who separated its oxide and is credited with...	1880	1886	J.C.G. de Marignac Jean Charles Galissard de Marignac Jean Charles Galissard de Marignac was a Swiss chemist whose work with atomic weights suggested the possibility of isotopes and the packing fraction of nuclei and whose study of the rare earth elements led to his discovery of ytterbium in 1878 and codiscovery of gadolinium in 1880.- Life and work...	F.L. de Boisbaudran	Marignac initially observed the new earth in terbia, and later Boisbaudran obtained a pure sample from samarskite Samarskite Samarskite is a radioactive rare earth mineral series which includessamarskite- with formula: 22O8and samarskite- with formula 22O8 The formula for smarskite- is also given as: O4... .
59	Praseodymium Praseodymium Praseodymium is a chemical element that has the symbol Pr and atomic number 59. Praseodymium is a soft, silvery, malleable and ductile metal in the lanthanide group. It is too reactive to be found in native form, and when artificially prepared, it slowly develops a green oxide coating.The element...	1885	?	C.A.von Welsbach Carl Auer von Welsbach Carl Auer Freiherr von Welsbach was an Austrian scientist and inventor who had a talent for not only discovering advances, but turning them into commercially successful products...	?	Von Welsbach discovered two new distinct elements in ceria: praseodymium and neodymium.
60	Neodymium Neodymium Neodymium is a chemical element with the symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite...	1885	?	C.A.von Welsbach Carl Auer von Welsbach Carl Auer Freiherr von Welsbach was an Austrian scientist and inventor who had a talent for not only discovering advances, but turning them into commercially successful products...	?	Von Welsbach discovered two new distinct elements in ceria: praseodymium and neodymium.
66	Dysprosium Dysprosium Dysprosium is a chemical element with the symbol Dy and atomic number 66. It is a rare earth element with a metallic silver luster. Dysprosium is never found in nature as a free element, though it is found in various minerals, such as xenotime...	1886	?	P.E.L. de Boisbaudran Paul Emile Lecoq de Boisbaudran Paul Émile Lecoq de Boisbaudran was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium.-Biography:...	?	De Boisbaudran found a new earth in erbia.
32	Germanium Germanium Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....	1886	?	C.A.Winkler Clemens Winkler Clemens Alexander Winkler was a German chemist who discovered the element germanium in 1886, solidifying Dmitri Mendeleev's theory of periodicity.- Life :...	?	In February 1886 Winkler found in argyrodite Argyrodite Argyrodite is an uncommon silver germanium sulfide mineral with formula Ag8GeS6. The color is iron-black with a purplish tinge, and the lustre metallic....  the eka-silicon that Mendeleev had predicted in 1871 Mendeleev's predicted elements Professor Dmitri Mendeleev published the first Periodic Table of the Atomic Elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest.... .
9	Fluorine Fluorine Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...	1886	1886	H.Moissan Henri Moissan Ferdinand Frederick Henri Moissan was a French chemist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds.-Biography:...	H.Moissan	Lavoisier predicted an element obtained from hydrofluoric acid Hydrofluoric acid Hydrofluoric acid is a solution of hydrogen fluoride in water. It is a valued source of fluorine and is the precursor to numerous pharmaceuticals such as fluoxetine and diverse materials such as PTFE .... , and between 1812 and 1886 many researchers tried to obtain this element. It was eventually isolated by Moissan.
18	Argon Argon Argon is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table . Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide...	1894	1894	Lord Rayleigh John Strutt, 3rd Baron Rayleigh John William Strutt, 3rd Baron Rayleigh, OM was an English physicist who, with William Ramsay, discovered the element argon, an achievement for which he earned the Nobel Prize for Physics in 1904...  & W.Ramsay William Ramsay Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...	Lord Rayleigh & W.Ramsay	They discovered the gas by comparing the molecular weights of nitrogen prepared by liquefaction Liquefaction Liquefaction may refer to:* Liquefaction, the general process of becoming liquid* Soil liquefaction, the process by which sediments become suspended* Liquefaction of gases in physics, chemistry, and thermal engineering* Liquefactive necrosis in pathology...  from air and nitrogen prepared by chemical means. It is the first noble gas to be isolated.
36	Krypton Krypton Krypton is a chemical element with the symbol Kr and atomic number 36. It is a member of Group 18 and Period 4 elements. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere, is isolated by fractionally distilling liquified air, and is often used with other...	1898	1898	W.Ramsay William Ramsay Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...  & M.W.Travers	W.Ramsay & M.W.Travers	On May 30, 1898, Ramsay separated a third noble gas from liquid argon by difference in boiling point.
10	Neon Neon Neon is the chemical element that has the symbol Ne and an atomic number of 10. Although a very common element in the universe, it is rare on Earth. A colorless, inert noble gas under standard conditions, neon gives a distinct reddish-orange glow when used in either low-voltage neon glow lamps or...	1898	1898	W.Ramsay William Ramsay Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...  & M.W.Travers	W.Ramsay & M.W.Travers	In June 1898 Ramsay separated a new noble gas from liquid argon by difference in boiling point.
54	Xenon Xenon Xenon is a chemical element with the symbol Xe and atomic number 54. The element name is pronounced or . A colorless, heavy, odorless noble gas, xenon occurs in the Earth's atmosphere in trace amounts...	1898	1898	W.Ramsay William Ramsay Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...  & M.W.Travers	W.Ramsay & M.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 Polonium Polonium is a chemical element with the symbol Po and atomic number 84, discovered in 1898 by Marie Skłodowska-Curie and Pierre Curie. A rare and highly radioactive element, polonium is chemically similar to bismuth and tellurium, and it occurs in uranium ores. Polonium has been studied for...	1898	1902	P.Curie Pierre Curie Pierre Curie was a French physicist, a pioneer in crystallography, magnetism, piezoelectricity and radioactivity, and Nobel laureate. He was the son of Dr. Eugène Curie and Sophie-Claire Depouilly Curie ...  & M.Curie Marie Curie Marie Skłodowska-Curie was a physicist and chemist famous for her pioneering research on radioactivity. She was the first person honored with two Nobel Prizes—in physics and chemistry...	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 Radium Radium is a chemical element with atomic number 88, represented by the symbol Ra. Radium is an almost pure-white alkaline earth metal, but it readily oxidizes on exposure to air, becoming black in color. All isotopes of radium are highly radioactive, with the most stable isotope being radium-226,...	1898	1902	P.Curie Pierre Curie Pierre Curie was a French physicist, a pioneer in crystallography, magnetism, piezoelectricity and radioactivity, and Nobel laureate. He was the son of Dr. Eugène Curie and Sophie-Claire Depouilly Curie ...  & M.Curie Marie Curie Marie Skłodowska-Curie was a physicist and chemist famous for her pioneering research on radioactivity. She was the first person honored with two Nobel Prizes—in physics and chemistry...	M. Curie	The Curies reported on December 26, 1898, a new element different from polonium, which Marie later isolated from uraninite Uraninite Uraninite is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2, but also contains UO3 and oxides of lead, thorium, and rare earth elements... .
86	Radon Radon Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium or thorium. Its most stable isotope, 222Rn, has a half-life of 3.8 days...	1898	1910	F.E.Dorn Friedrich Ernst Dorn Friedrich Ernst Dorn was a German physicist who was the first to discover that a radioactive substance, later named radon, is emitted from radium.-Life and work:...	W.Ramsay William Ramsay Sir William Ramsay was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air" .-Early years:Ramsay was born in Glasgow on 2...  & R.Whytlaw-Gray Robert Whytlaw-Gray Robert H. Whytlaw-Gray was a chemist, born in London, England. He studied at University of Glasgow and University College London. He and William Ramsay isolated radon and studied its physical properties .-Biography:...	Dorn discovered a radioactive gas resulting from the radioactive decay of radium, isolated later by Ramsay and Gray.
89	Actinium Actinium Actinium is a radioactive chemical element with the symbol Ac and atomic number 89, which was discovered in 1899. It was the first non-primordial radioactive element to be isolated. Polonium, radium and radon were observed before actinium, but they were not isolated until 1902...	1899	1899	A.-L.Debierne André-Louis Debierne André-Louis Debierne was a French chemist and is considered the discoverer of the element actinium....	A.-L.Debierne	Debierne obtained from pitchblende a substance that had properties similar to those of thorium.
63	Europium Europium Europium is a chemical element with the symbol Eu and atomic number 63. It is named after the continent of Europe. It is a moderately hard silvery metal which readily oxidizes in air and water...	1896	1901	E.Demarcay	E.Demarçay	Demarçay found spectral lines of a new element in Lecoq's samarium, and separated this element several years later.
71	Lutetium	1906	1906	G.Urbain Georges Urbain Georges Urbain - French chemist, professor of Sorbonne. He studied at the elite École supérieure de physique et de chimie industrielles de la ville de Paris . He discovered the element Lutetium in 1907.-References:... , C.A. von Welsbach Carl Auer von Welsbach Carl Auer Freiherr von Welsbach was an Austrian scientist and inventor who had a talent for not only discovering advances, but turning them into commercially successful products...	G. Urbain & C.A. von Welsbach	Urbain and von Welsbach proved independently that the old ytterbium Ytterbium Ytterbium is a chemical element with the symbol Yb and atomic number 70. A soft silvery metallic element, ytterbium is a rare earth element of the lanthanide series and is found in the minerals gadolinite, monazite, and xenotime. The element is sometimes associated with yttrium or other related...  also contained a new element.
75	Rhenium Rhenium Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an average concentration of 1 part per billion , rhenium is one of the rarest elements in the Earth's crust. The free element has...	1908	1908	M.Ogawa Masataka Ogawa was a Japanese chemist known for the discovery of rhenium, which he named nipponium.After graduating from the University of Tokyo, he studied under William Ramsay in London, where he worked on the analysis of the rare mineral thorianite...	M.Ogawa	Ogawa found it in thorianite Thorianite Thorianite is a rare mineral, originally discovered by Ananda Coomaraswamy in 1904 as uraninite, but recognized as a new species by Wyndham R. Dunstan. It was so named on account of its high percentage of thorium ; it also contains the oxides of uranium, lanthanum, cerium and didymium...  but assigned it as element 43 instead of 75 and named it nipponium. In 1922 Walter Noddack Walter Noddack Walter Noddack was a German chemist. He, Ida Tacke , and Otto Berg reported the discovery of element 43 and element 75 in 1925.-Rhenium:... , Ida Eva Tacke Ida Noddack Ida Noddack , née Ida Tacke, was a German chemist and physicist. She was the first to mention the idea of nuclear fission in 1934. With her husband Walter Noddack she discovered element 75 rhenium...  and Otto Berg Otto Berg (scientist) Otto Berg was a German scientist. He is one of the scientists credited with discovering rhenium, the next-to-last naturally occurring element to be discovered and the last element to be discovered having a stable isotope.-Rhenium:...  announced its separation from gadolinite Gadolinite Gadolinite, sometimes also known as Ytterbite, is a silicate mineral which consists principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron with the formula 2FeBe2Si2O10...  and gave it the present name.
72	Hafnium Hafnium Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869. Hafnium was the penultimate stable...	1911	1922	G.Urbain Georges Urbain Georges Urbain - French chemist, professor of Sorbonne. He studied at the elite École supérieure de physique et de chimie industrielles de la ville de Paris . He discovered the element Lutetium in 1907.-References:... , V.I.Vernadsky Vladimir Vernadsky Vladimir Ivanovich Vernadsky was a Russian/Ukrainian and Soviet mineralogist and geochemist who is considered one of the founders of geochemistry, biogeochemistry, and of radiogeology. His ideas of noosphere were an important contribution to Russian cosmism. He also worked in Ukraine where he...	D.Coster Dirk Coster Dirk Coster , was a Dutch physicist. He was a Professor of Physics and Meteorology at the University of Groningen....  & G. von Hevesy	Urbain claimed to have found the element in rare-earth residues, while Vernadsky Vladimir Vernadsky Vladimir Ivanovich Vernadsky was a Russian/Ukrainian and Soviet mineralogist and geochemist who is considered one of the founders of geochemistry, biogeochemistry, and of radiogeology. His ideas of noosphere were an important contribution to Russian cosmism. He also worked in Ukraine where he...  independently found it in orthite. Neither claim was confirmed due to World War I World War I World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918... . After the war, Coster and Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon. It is the last stable element to be discovered.
91	Protactinium Protactinium Protactinium is a chemical element with the symbol Pa and atomic number 91. It is a dense, silvery-gray metal which readily reacts with oxygen, water vapor and inorganic acids. It forms various chemical compounds where protactinium is usually present in the oxidation state +5, but can also assume...	1913	?	O.H.Göhring, K.Fajans	?	The two obtained the first isotope of this element that had been predicted by Mendeleev in 1871 Mendeleev's predicted elements Professor Dmitri Mendeleev published the first Periodic Table of the Atomic Elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest....  as a member of the natural decay of 238U. Originally isolated in 1900 by William Crookes William Crookes Sir William Crookes, OM, FRS was a British chemist and physicist who attended the Royal College of Chemistry, London, and worked on spectroscopy... .
43	Technetium Technetium Technetium is the chemical element with atomic number 43 and symbol Tc. It is the lowest atomic number element without any stable isotopes; every form of it is radioactive. Nearly all technetium is produced synthetically and only minute amounts are found in nature...	1937	1937	C.Perrier Carlo Perrier Carlo Perrier was an Italian mineralogist who did extensive research on the element technetium in 1936. He discovered the element along with his colleague, Emilio Segrè , in 1937.... , E.Segrè	C.Perrier & E.Segrè	The two discovered a new element in a molybdenum sample that was used in a cyclotron Cyclotron In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction... , the first synthetic element Synthetic element In chemistry, a synthetic element is a chemical element that is too unstable to occur naturally on Earth, and therefore has to be created artificially. So far 30 synthetic elements have been discovered—that is, synthesized...  to be discovered. It had been predicted by Mendeleev in 1871 Mendeleev's predicted elements Professor Dmitri Mendeleev published the first Periodic Table of the Atomic Elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest....  as eka-manganese.
87	Francium Francium Francium is a chemical element with symbol Fr and atomic number 87. It was formerly known as eka-caesium and actinium K.Actually the least unstable isotope, francium-223 It has the lowest electronegativity of all known elements, and is the second rarest naturally occurring element...	1939	1939	M.Perey Marguerite Perey Marguerite Catherine Perey was a French physicist. In 1939, Perey discovered the element francium by purifying samples of lanthanum that contained actinium. She was a student of Marie Curie...	M.Perey	Perey discovered it as a decay product of 227Ac. Francium is the last element to be discovered in nature, rather than synthesized in the lab, although some of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine) were eventually found in trace amounts in nature as well.
85	Astatine Astatine Astatine is a radioactive chemical element with the symbol At and atomic number 85. It occurs on the Earth only as the result of decay of heavier elements, and decays away rapidly, so much less is known about this element than its upper neighbors in the periodic table...	1940	?	D.R.Corson Dale R. Corson Dale R. Corson was the eighth president of Cornell University. Born in Pittsburg, Kansas, in 1914, Corson received a B.A. degree from the College of Emporia in 1934, his M.A. degree from the University of Kansas in 1935, and his Ph.D... , K.R.Mackenzie, E.Segrè	?	Obtained by bombarding bismuth with alpha particles. Later determined to occur naturally in minuscule quantitites (<25 grams in earth's crust).
93	Neptunium Neptunium Neptunium is a chemical element with the symbol Np and atomic number 93. A radioactive metal, neptunium is the first transuranic element and belongs to the actinide series. Its most stable isotope, 237Np, is a by-product of nuclear reactors and plutonium production and it can be used as a...	1940	?	E.M. McMillan Edwin McMillan Edwin Mattison McMillan was an American physicist and Nobel laureate credited with being the first ever to produce a transuranium element. He shared the Nobel Prize in Chemistry with Glenn Seaborg in 1951.... , P.H.Abelson	?	Obtained by irradiating uranium with neutrons, it is the first transuranium element Transuranium element In chemistry, transuranium elements are the chemical elements with atomic numbers greater than 92...  discovered.
94	Plutonium Plutonium Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...	1940-1	?	G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the... , Arthur C. Wahl Arthur Wahl Arthur C. Wahl was an American chemist who, as a PhD student of Glenn T. Seaborg at UC Berkeley, first isolated plutonium in February 1941. He also worked on the Manhattan Project.- Further readings :... , J.W.Kennedy Joseph W. Kennedy Joseph William Kennedy was an American scientist credited with being a co-discoverer of plutonium along with Glenn T. Seaborg, Edwin McMillan, and Arthur Wahl.... , E.M.McMillan	?	Prepared by bombardment of uranium with deuterons.
95	Americium Americium Americium is a synthetic element that has the symbol Am and atomic number 95. This transuranic element of the actinide series is located in the periodic table below the lanthanide element europium, and thus by analogy was named after another continent, America.Americium was first produced in 1944...	1944	?	G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the... , R.A.James, L.O.Morgan & A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:...	?	Prepared by irradiating plutonium with neutrons during the Manhattan Project Manhattan Project The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army... .
96	Curium Curium Curium is a synthetic chemical element with the symbol Cm and atomic number 96. This radioactive transuranic element of the actinide series was named after Marie Skłodowska-Curie and her husband Pierre Curie. Curium was first intentionally produced and identified in summer 1944 by the group of...	1944	?	G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the... , R.A.James, A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:...	?	Prepared by bombarding plutonium with alpha particles during the Manhattan Project Manhattan Project The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
61	Promethium Promethium Promethium is a chemical element with the symbol Pm and atomic number 61. It is notable for being the only exclusively radioactive element besides technetium that is followed by chemical elements with stable isotopes.- Prediction :...	1942	1945	C.S.Wu, E.G.Segrè Emilio G. Segrè Emilio Gino Segrè was an Italian-born, naturalized American, physicist and Nobel laureate in physics, who with Owen Chamberlain, discovered antiprotons, a sub-atomic antiparticle.-Biography:... , H.A.Bethe	Charles D. Coryell Charles D. Coryell Charles DuBois Coryell was an American chemist who was one of the discoverers of the element promethium.... , Jacob A. Marinsky Jacob A. Marinsky Jacob Akiba Marinsky was a chemist who was the co-discoverer of the element promethium.Marinsky was born in Buffalo, New York, and attended the University at Buffalo, entering at age 16 and receiving a bachelor's degree in chemistry in 1939.During World War II he was employed as a chemist for the... , Lawrence E. Glendenin Lawrence E. Glendenin Lawrence Elgin Glendenin was an American chemist who co-discovered the element promethium.- Biography :Glendenin was born in Bay City, Michigan on November 8, 1918... , Harold G. Richter	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 Manhattan Project The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...  in 1945.
97	Berkelium Berkelium Berkelium , is a synthetic element with the symbol Bk and atomic number 97, a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the University of California Radiation Laboratory where it was discovered in December 1949...	1949	?	S.G.Thompson, A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the... (University of California, Berkeley University of California, Berkeley The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA... )	?	Created by bombardment of americium with alpha particles.
98	Californium Californium Californium is a radioactive metallic chemical element with the symbol Cf and atomic number 98. The element was first made in the laboratory in 1950 by bombarding curium with alpha particles at the University of California, Berkeley. It is the ninth member of the actinide series and was the...	1950	?	S.G.Thompson, K.Street,Jr. Kenneth Street, Jr. Kenneth Street, Jr. was an American chemist. He was part of the team that discovered elements 97 and 98 in 1949 and 1950.... , A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the...   (University of California, Berkeley University of California, Berkeley The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA... )	?	Bombardment of curium with alpha particles.
99	Einsteinium Einsteinium Einsteinium is a synthetic element with the symbol Es and atomic number 99. It is the seventh transuranic element, and an actinide.Einsteinium was discovered in the debris of the first hydrogen bomb explosion in 1952, and named after Albert Einstein...	1952	1952	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... et al. (Argonne Laboratory, Los Alamos Laboratory, and University of California, Berkeley University of California, Berkeley The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA... )		Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons; kept secret for several years.
100	Fermium Fermium Fermium is a synthetic element with the symbol Fm. It is the 100th element in the periodic table and a member of the actinide series. It is the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities,...	1952	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... et al. (Argonne Laboratory, Los Alamos Laboratory, and University of California, Berkeley University of California, Berkeley The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA... )		Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons; kept secret for several years.
101	Mendelevium Mendelevium Mendelevium is a synthetic element with the symbol Md and the atomic number 101. A metallic radioactive transuranic element in the actinide series, mendelevium is usually synthesized by bombarding einsteinium with alpha particles. It was named after Dmitri Ivanovich Mendeleev, who created the...	1955	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , B.G.Harvey, G.R.Choppin, S.G.Thompson, G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the...	?	Prepared by bombardment of einsteinium with helium.
102	Nobelium Nobelium Nobelium is a synthetic element with the symbol No and atomic number 102. It was first correctly identified in 1966 by scientists at the Flerov Laboratory of Nuclear Reactions in Dubna, Soviet Union...	1958	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , T.Sikkeland, J.R.Walton, G.T.Seaborg Glenn T. Seaborg Glenn Theodore Seaborg was an American scientist who won the 1951 Nobel Prize in Chemistry for "discoveries in the chemistry of the transuranium elements", contributed to the discovery and isolation of ten elements, and developed the actinide concept, which led to the current arrangement of the...	?	First prepared by bombardment of curium with carbon atoms.
103	Lawrencium Lawrencium Lawrencium is a radioactive synthetic chemical element with the symbol Lr and atomic number 103. In the periodic table of the elements, it is a period 7 d-block element and the last element of actinide series...	1961	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , T.Sikkeland, A.E.Larsh, R.M.Latimer	?	First prepared by bombardment of californium with boron atoms.
104	Rutherfordium Rutherfordium Rutherfordium is a chemical element with symbol Rf and atomic number 104, named in honor of New Zealand physicist Ernest Rutherford. It is a synthetic element and radioactive; the most stable known isotope, 267Rf, has a half-life of approximately 1.3 hours.In the periodic table of the elements,...	1968	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , M.Nurmia, J.Harris, K.Eskola, P.Eskola	?	Prepared by bombardment of californium with carbon atoms.
105	Dubnium Dubnium The Soviet team proposed the name nielsbohrium in honor of the Danish nuclear physicist Niels Bohr. The American team proposed that the new element should be named hahnium , in honor of the late German chemist Otto Hahn...	1970	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , M.Nurmia, K.Eskola, J.Harris, P.Eskola	?	Prepared by bombardment of californium with nitrogen atoms.
106	Seaborgium Seaborgium Seaborgium is a synthetic chemical element with the symbol Sg and atomic number 106.Seaborgium is a synthetic element whose most stable isotope 271Sg has a half-life of 1.9 minutes. A new isotope 269Sg has a potentially slightly longer half-life based on the observation of a single decay...	1974	?	A.Ghiorso Albert Ghiorso Albert Ghiorso was an American nuclear scientist and co-discoverer of a record 12 chemical elements on the periodic table. His research career spanned five decades, from the early 1940s to the late 1990s.-Early life:... , J.Nitschke, J.Alonso, C.Alonso, M.Nurmia, G. Seaborg, K.Hulet, R.W.Lougheed	?	Prepared by collisions of californium-249 with oxygen atoms.
107	Bohrium Bohrium Bohrium is a chemical element with the symbol Bh and atomic number 107 and is the heaviest member of group 7 .It is a synthetic element whose most stable known isotope, 270Bh, has a half-life of 61 seconds...	1981	?	G.Münzenberg Gottfried Münzenberg Gottfried Münzenberg is a German physicist.He studied physics at Justus-Liebig-Universität in Giessen and Leopold-Franzens-Universität Innsbruck and completed his studies with a Ph.D. at the University of Giessen, Germany, in 1971... et al. GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Obtained by bombarding bismuth with chromium.
109	Meitnerium Meitnerium Meitnerium is a chemical element with the symbol Mt and atomic number 109. It is placed as the heaviest member of group 9 in the periodic table but a sufficiently stable isotope is not known at this time which would allow chemical experiments to confirm its position, unlike its lighter...	1982	?	G.Münzenberg Gottfried Münzenberg Gottfried Münzenberg is a German physicist.He studied physics at Justus-Liebig-Universität in Giessen and Leopold-Franzens-Universität Innsbruck and completed his studies with a Ph.D. at the University of Giessen, Germany, in 1971... , P.Armbruster Peter Armbruster Peter Armbruster is a physicist at the Gesellschaft für Schwerionenforschung facility in Darmstadt, Germany, and is credited with co-discovering elements 107 , 108 , 109 , 110 , 111 , and 112 with research partner Gottfried Münzenberg.He studied physics at the Technical... et al. GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Prepared by bombardment of bismuth with iron atoms.
108	Hassium Hassium Hassium is a synthetic element with the symbol Hs and atomic number 108. It is the heaviest member of the group 8 elements. The element was first observed in 1984...	1984	?	G.Münzenberg Gottfried Münzenberg Gottfried Münzenberg is a German physicist.He studied physics at Justus-Liebig-Universität in Giessen and Leopold-Franzens-Universität Innsbruck and completed his studies with a Ph.D. at the University of Giessen, Germany, in 1971... , P.Armbruster Peter Armbruster Peter Armbruster is a physicist at the Gesellschaft für Schwerionenforschung facility in Darmstadt, Germany, and is credited with co-discovering elements 107 , 108 , 109 , 110 , 111 , and 112 with research partner Gottfried Münzenberg.He studied physics at the Technical... et al. at GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Prepared by bombardment of lead with iron atoms
110	Darmstadtium Darmstadtium Darmstadtium is a chemical element with the symbol Ds and atomic number 110. It is placed as the heaviest member of group 10, but no known isotope is sufficiently stable to allow chemical experiments to confirm its placing in that group...	1994	?	S.Hofmann et al. at GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Prepared by bombardment of lead with nickel.
111	Roentgenium Roentgenium Roentgenium is a synthetic radioactive chemical element with the symbol Rg and atomic number 111. It is placed as the heaviest member of the group 11 elements, although a sufficiently stable isotope has not yet been produced in a sufficient amount that would confirm this position as a heavier...	1994	?	S.Hofmann et al. at GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Prepared by bombardment of bismuth with nickel.
112	Copernicium	1996	?	S.Hofmann et al. at GSI in Darmstadt Gesellschaft für Schwerionenforschung The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...	?	Prepared by bombardment of lead with zinc.
114	Ununquadium Ununquadium Ununquadium is the temporary name of a radioactive chemical element with the temporary symbol Uuq and atomic number 114. There is no proposed name yet, although flerovium has been discussed in the media.About 80 decays of atoms of...	1999	?	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna Dubna Dubna is a town in Moscow Oblast, Russia. It has a status of naukograd , being home to the Joint Institute for Nuclear Research, an international nuclear physics research centre and one of the largest scientific foundations in the country. It is also home to MKB Raduga, a defence aerospace company...	?	Prepared by bombardment of plutonium with calcium
116	Ununhexium Ununhexium Ununhexium is the temporary name of a synthetic superheavy element with the temporary symbol Uuh and atomic number 116. There is no proposed name yet although moscovium has been discussed in the media.It is placed as the heaviest member of group 16 although a sufficiently stable isotope is...	2000	?	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna Dubna Dubna is a town in Moscow Oblast, Russia. It has a status of naukograd , being home to the Joint Institute for Nuclear Research, an international nuclear physics research centre and one of the largest scientific foundations in the country. It is also home to MKB Raduga, a defence aerospace company...	?	Prepared by bombardment of curium with calcium

Recent discoveries

Unconfirmed discoveries

Z	Name	Discovery year	Discoverer	Notes
118	Ununoctium Ununoctium Ununoctium is the temporary IUPAC name for the transactinide element having the atomic number 118 and temporary element symbol Uuo. It is also known as eka-radon or element 118, and on the periodic table of the elements it is a p-block element and the last one of the 7th period. Ununoctium is...	2002	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna and Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...	Prepared by bombardment of californium with calcium
113	Ununtrium Ununtrium Ununtrium is the temporary name of a synthetic element with the temporary symbol Uut and atomic number 113.It is placed as the heaviest member of the group 13 elements although a sufficiently stable isotope is not known at this time that would allow chemical experiments to confirm its position...	2003	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna and Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...	Decay of ununpentium
115	Ununpentium Ununpentium Ununpentium is the temporary name of a synthetic superheavy element in the periodic table that has the temporary symbol Uup and has the atomic number 115....	2003	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna and Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...	Prepared by bombardment of americium with calcium
117	Ununseptium Ununseptium Ununseptium is the temporary name of a superheavy artificial chemical element with temporary symbol Uus and atomic number 117. Six atoms were detected by a joint Russia–US collaboration at Dubna, Moscow Oblast, Russia, in 2009–10...	2010	Joint Institute for Nuclear Research Joint Institute for Nuclear Research The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow Oblast , Russia, is an international research centre for nuclear sciences, with 5500 staff members, 1200 researchers including 1000 Ph.D.s from eighteen member states The Joint Institute for Nuclear Research, JINR , in Dubna, Moscow...  in Dubna and Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...	Prepared by bombardment of berkelium with calcium

External links

• http://www.nndc.bnl.gov/content/elements.html
• History of Elements of the Periodic Table
• Timeline of Element Discoveries