AtomicNumber	Name	Symbol	Period	Group	AtomicWeight	WeightApprox	ShellConfig	Discovered	DiscoveryOrdinal	NameOrigin	SymbolOrigin
1	Hydrogen	H	1	1	1.00794	0	1s(1)	%E% was discovered in 1766, by Henry Cavendish.	1766	It derives its name from the Greek phrase “hydro genes” (water-forming), so named by the French chemist Lavoisier in recognition of the discovery by Cavendish that when burned, hydrogen produces water.	
2	Helium	He	1	18	4.0026	0	1s(2)	%E% was discovered in 1868, by Pierre J.C. Janssen, during observations of the sun made in India during a solar eclipse; and separately by Norman Lockyer and Edward Frankland, during solar observations in London.	1868	It derives its name from the Greek word “helios” (sun), where it was first discovered.	
3	Lithium	Li	2	1	6.941	0	1s(2)2s(1)	%E% was discovered in 1817, by Johan August Arfvedson, Stockholm, Sweden.	1817.1	It derives its name from the Greek word “lithos” (stone), after the fact that it was discovered in a sample of stone (petalite).	
4	Beryllium	Be	2	2	9.01218	0	1s(2)2s(2)	%E% was discovered in 1798, by Nicholas Louis Vaquelin.	1797	It derives its name from “beryllo”, the Greek word for beryl (beryllium aluminum cyclosilicate).	
5	Boron	B	2	13	10.811	0	1s(2)2s(2)2p(1)	%E% was first isolated in 1808, by Sir Humphry Davy, Joseph-Louis Gay-Lussac, and Louis Jacques Thénard.	1808.1	It derives its name from the Arabic word “buraq” (borax).	
6	Carbon	C	2	14	12.011	0	1s(2)2s(2)2p(2)	%E% has been known since antiquity.	-9999	It derives its name from the Latin word “carbo” (charcoal).	
7	Nitrogen	N	2	15	14.0067	0	1s(2)2s(2)2p(3)	%E% was discovered in 1772, by Daniel Rutherford, in Edinburgh, Scotland.	1772.1	It derives its name from the Greek phrase “nitron genes” (nitre-forming), from its presence in potassium nitrate, also known as nitre or saltpeter.	
8	Oxygen	O	2	16	15.9994	0	1s(2)2s(2)2p(4)	%E% was discovered in 1774, by Joseph Priestly, in England; and in 1775, by Carl Wilhelm Scheele, in Sweden.	1772.2	It derives its name from the Greek phrase “oxy genes” (acid-forming), from the incorrect  belief that all acids contain oxygen.	
9	Fluorine	F	2	17	18.9984	0	1s(2)2s(2)2p(5)	%E% was discovered in 1886, by Henri Moissan, in Paris, France (named earlier in the nineteenth century by Sir Humphry Davy, who was unable to isolate it.).	1886.2	It derives its name from the Latin word “fluere” (to flow), from the fact that fluorspar (calcium fluoride) melts when heated in a flame.	
10	Neon	Ne	2	18	20.1797	0	1s(2)2s(2)2p(6)	%E% was discovered in 1898, by William Ramsay and Morris Travers, University College, London.	1898.2	It derives its name from the Greek word “neos“ (“new”).	
11	Sodium	Na	3	1	22.98977	0	(Ne) 3s(1)	%E% was discovered in 1807, by Humphry Davy, Royal Institution, London, England.	1807	It derives its name from the word “soda“ (sodium carbonate). Soda may have derived from “sodanum“, a headache remedy in the Roman Empire, which in turn may have derived from the Arabic word “suda“ (headache or split).	Latin: natrium (“soda”).
12	Magnesium	Mg	3	2	24.305	0	(Ne) 3s(2)	%E% was discovered in 1755, by Joseph Black, Edinburgh, Scotland.	1755	It was named for Magnesia, in Thessaly, Greece, a source of magnesium ores since antiquity.	
13	Aluminum	Al	3	13	26.98154	0	(Ne) 3s(2)3p(1)	Humphry Davy verified the existence of %e% in 1808, and gave the element its name. It was subsequently isolated in 1825 by Hans Christian Ørsted (Denmark).	1825.1	It derives its name from the Latin word “alumen“ (“bitter salt”), an ancient name for alum (potassium aluminum sulfate).	
14	Silicon	Si	3	14	28.0855	0	(Ne) 3s(2)3p(2)	%E% was discovered in 1824, by Jöns Jacob Berzelius, Stockholm, Sweden.	1824	It derives its name from the Latin word “silex“ or “silicis“ (“flint”), from which it was first isolated.	
15	Phosphorus	P	3	15	30.97376	0	(Ne) 3s(2)3p(3)	%E% was discovered in 1669, by Henning Brand, Hamburg, Germany.	1669	It derives its name from the Greek phrase “phos phoros“ (“light bringer”), from the fact that solid and liquid phosphorus glows as its surface reacts with oxygen.	
16	Sulfur	S	3	16	32.066	0	(Ne) 3s(2)3p(4)	%E% has been known since antiquity.	-9997	It derives its name from the Sanskrit word “sulvere“, or the Latin word “sulfurium“ (“sulfur”).	
17	Chlorine	Cl	3	17	35.4527	0	(Ne) 3s(2)3p(5)	%E% was discovered in 1774, by Carl Wilhelm Scheele, Uppsala, Sweden.	1774.1	It derives its name from the Greek word “chloros“ (“greenish yellow”), from its color.	
18	Argon	Ar	3	18	39.948	0	(Ne) 3s(2)3p(6)	%E% was discovered in 1894 by John Strutt, the third Lord Rayleigh; and Sir William Ramsay.	1884	It derives its name from the Greek word “argos“ (“idle” or “lazy one”), a reference to argon's chemical inactivity.	
19	Potassium	K	4	1	39.0983	0	(Ar) 4s(1)	%E% was discovered in 1807, by Humphry Davy.	1807	It derives its name from the word “potash“ (potassium carbonate), used since antiquity in soap- and glass-making. The word potash derives from the fact that it was obtained from wood ash by a process of leaching and evaporation which was typically performed in an iron pot.	Latin: “kalium“ (“potash”), possibly from Arabic: “qali“ (“alkali”; potash is an alkali), in turn derived from “qalay“ (“to fry in a pan”); thus “al-qali“ means “the substance being roasted”, a reference to the fact that alkalis are found in ash.
20	Calcium	Ca	4	2	40.078	0	(Ar) 4s(2)	%E% was discovered in 1808 by Humphry Davy.	1808.2	It derives its name from the Latin word “calx“ (“lime”), or calcium carbonate.	
21	Scandium	Sc	4	3	44.9559	0	(Ar) 3d(1)4s(2)	%E% was discovered in 1879, by Lars Frederick Nilson, University of Uppsala, Sweden.	1879.1	It derives its name from Scandia, the Latin word for Scandinavia, from the region where it was discovered.	
22	Titanium	Ti	4	4	47.88	0	(Ar) 3d(2)4s(2)	%E% was discovered in 1795, by Martin Heinrich Klaproth, Berlin, Germany.	1791	It is named for the Titans, sons of the Earth goddess in Greek mythology. Klaproth could not discern any notable characteristics of the new element, and so deliberately gave it a name with no meaning.	
23	Vanadium	V	4	5	50.9415	0	(Ar) 3d(3)4s(2)	%E% was discovered in 1801, by Andrés Manuel del Rio, Mexico City, Mexico.	1801.1	It is named for Vanadis, Scandinavian goddess of beauty, for the variety of colors in its salts. Chromium was named for the same reason (the Greek word “chroma“ = color).	
24	Chromium	Cr	4	6	51.996	0	(Ar) 3d(5)4s(1)	%E% was discovered in 1798, by Nicholas Louis Vauquelin, in Paris, France.	1780	It derives its name from the Greek word “chroma“ (“color”), from its colorful salts. Vanadium was named for the same reason (for Vanadis, the Scandinavian goddess of beauty).	
25	Manganese	Mn	4	7	54.938	0	(Ar) 3d(5)4s(2)	Compounds of %e% were used in antiquity, but it was first identified as an element by Carl Wilhelm Scheele in 1774, and was first isolated in the same year by Scheele's colleague Johan Gottlieb Gahn.	1774.2	It is named for Magnesia, in Thessaly, Greece, a source of magnesium ores since antiquity; possibly also Italian, corruption of “magnesia”.	
26	Iron	Fe	4	8	55.847	0	(Ar) 3d(6)4s(2)	%E% has been known since antiquity.	-2500	It derives its name from the Anglo-Saxon word “iren“ or “isern“ (“iron”).	Latin: ferrum (“iron”).
27	Cobalt	Co	4	9	58.9332	0	(Ar) 3d(7)4s(2)	%E% was discovered in 1730, by Georg Brandt, Stockholm, Sweden.	1735	It derives its name from the German word for cobalt arsenide, “kobald“ (“goblin”), which in turn is derived from the Greek word “cobalos“ (“mine”). Cobalt arsenide was thought by sixteenth century Saxony miners to be a silver ore; when they found only toxic fumes they believed the ore to be bewitched and called it kobald. (Nickel was named for similar reasons.)	
28	Nickel	Ni	4	10	58.6934	0	(Ar) 3d(8)4s(2)	%E% was discovered in 1751, by Alex Fredrik Cronstedt, Stockholm, Sweden.	1751	It derives its name from the German word “kupfernickel“ (“St. Nicholas' [devil's] copper”), so named because Saxon miners often mistook niccolite (a reddish ore containing arsenic and nickel) for a copper ore, and upon failing to extract copper, cursed it as bewitched. (Cobalt was named for similar reasons.).	
29	Copper	Cu	4	11	63.546	0	(Ar) 3d(10)4s(1)	%E% has been known since antiquity.	-9998	It derives its name from the Old English word “coper“ (“copper”), which is derived from the Latin phrase “Cyprium aes“ (“Cypriot metal”), and the Greek word “Kupros“ (“Cyprus”). Cyprus was a major metal exporter.	Greek: “Kupros“ (“Cyprus”).
30	Zinc	Zn	4	12	65.39	0	(Ar) 3d(10)4s(2)	%E% has been known since antiquity.; first identified as an element in 1746, by Andreas Marggraf, Germany.	1200	It derives its name from the German word “zink“ (“sharp point”), from the shapes formed by the metal when melting; or perhaps from the Persian word “sing“ (“stone”).	
31	Gallium	Ga	4	13	69.723	0	(Ar) 3d(10)4s(2)4p(1)	%E% was discovered in 1875, by Paul-Émile Lecoq de Boisbaudran, Paris, France.	1875	It derives its name from Gallia, the Latin word for France, where it was discovered. With francium, one of two elements named for France.	
32	Germanium	Ge	4	14	72.61	0	(Ar) 3d(10)4s(2)4p(2)	%E% was discovered in 1886, by Clemens A. Winkler, Freiberg, Germany.	1886.1	It derives its name from Germania, the Latin word for Germany, where it was discovered.	
33	Arsenic	As	4	15	74.9216	0	(Ar) 3d(10)4s(2)4p(3)	%E% was discovered in 1250 by Albertus Magnus.	1250	It derives its name from the Greek word “arsenikon“ and the Persian word “al-zarnik“, both of which mean “yellow orpiment”, and old name for arsenic sulfide.	
34	Selenium	Se	4	16	78.96	0	(Ar) 3d(10)4s(2)4p(4)	%E% was discovered in 1817, by Jöns Jacob Berzelius, Stockholm, Sweden.	1817.2	It derives its name from “selene“, the Greek word for the Moon, for its similarity to tellurium (named for the Earth).	
35	Bromine	Br	4	17	79.904	0	(Ar) 3d(10)4s(2)4p(5)	%E% was discovered in 1826, by Antoine-Jérôme Balard, Montpellier, France.	1825.2	It derives its name from the Greek word “bromos“ (“stench”).	
36	Krypton	Kr	4	18	83.8	0	(Ar) 3d(10)4s(2)4p(6)	%E% was discovered in 1898, by William Ramsay and Morris William Travers, London.	1898.1	It derives its name from the Greek word “kryptos“ (“hidden”), so named because it was isolated by evaporation from a sample of argon.	
37	Rubidium	Rb	5	1	85.4678	0	(Kr) 5s(1)	%E% was discovered in 1861, by Robert Wilhelm Bunsen and Gustav Robert Kirchoff, University of Heidelberg, Germany.	1861.1	It derives its name from the Latin word “rubidius“ (“deepest red”, or ruby red), from the color of two distinctive lines in its spectrum.	
38	Strontium	Sr	5	2	87.62	0	(Kr) 5s(2)	%E% was discovered in 1787, by Adair Crawford, Edinburgh, Scotland.	1808.3	It is named for strontianite, the mineral from which it was first isolated, which in turn was named for the mining town of Strontian, Scotland.	
39	Yttrium	Y	5	3	88.9059	0	(Kr) 4d(1)5s(2)	%E% was discovered in 1794, by Johan Gadolin, University of Åbo, Finland.	1794	It is one of four elements named for the town of Ytterby, Sweden (The other three are erbium, terbium, and ytterbium.) Yttrium was discovered near Ytterby; the sample was later found to be impure yttrium oxide, from which the other three elements were eventually isolated.	
40	Zirconium	Zr	5	4	91.224	0	(Kr) 4d(2)5s(2)	%E% was discovered in 1789, by Martin Heinrich Klaproth, Berlin, Germany, but first isolated in 1824 by Jöns Jakob Berzelius, in Sweden.	1788	It derives its name from the Arabic word “zargun“ (“gold colored”), from the color of one of type of the semi-precious gemstone zircon (zirconium silicate).	
41	Niobium	Nb	5	5	92.9064	0	(Kr) 4d(4)5s(1)	%E% was discovered in 1801, by Charles Hatchett, in London.	1801.2	It is named for Niobe, daughter of king Tantalus in Greek mythology, for its similarity to tantalum.	
42	Molybdenum	Mo	5	6	95.94	0	(Kr) 4d(5)5s(1)	%E% was discovered in 1778, Carl Wilhelm Scheele, in Sweden, and first isolated in 1781, by Peter Jacob Hjelm, Uppsala, Sweden.	1781	It derives its name from the Greek word “molybdos“ (“lead-like”), for the fact that was often confused with lead ores.	
43	Technetium	Tc	5	7	99	1	(Kr) 4d(5)5s(2)	%E% was discovered in 1937, by Carlo Perrier and Emilio Segrè, University of Palermo, Sicily, Italy.	1925.2	It derives its name from the Greek word “tekhnetos“ (“artificial”), so named because it is one of only two elements lighter than uranium that do not exist in nature due to their radioactivity (the other is promethium).	
44	Ruthenium	Ru	5	8	101.07	0	(Kr) 4d(7)5s(1)	%E% was discovered in 1840, by Karl Karlovich Klaus, at the University of Kazan, Russia.	1808.4	It derives its name from Ruthenia, the Latin name for Russia, from the country of its discovery.	
45	Rhodium	Rh	5	9	102.9055	0	(Kr) 4d(8)5s(1)	%E% was discovered in 1803, by William Hyde Wollaston, England.	1803.1	It derives its name from the Greek word “rhodon“ (“rose colored”), from the color of rhodium chloride crystals.	
46	Palladium	Pd	5	10	106.42	0	(Kr) 4d(10)	%E% was discovered in 1802, by William Hyde Wollaston, London, England.	1803.2	It was named after the asteroid Pallas, which has just been discovered.	
47	Silver	Ag	5	11	107.868	0	(Kr) 4d(10)5s(1)	%E% has been known since antiquity.	-5001	It derives its name from the Anglo-Saxon word “siolfur“ (“silver”).	Latin: argentum (“silver”), possibly derived from Sanskrit: arj-una (“light”).
48	Cadmium	Cd	5	12	112.41	0	(Kr) 4d(10)5s(2)	%E% was discovered in 1817, by Friedrich Strohmeyer.	1817.3	It derives its name from the Latin word “cadmia“ (“calamine”), or zinc carbonate, in which cadmium was first discovered as an impurity.	
49	Indium	In	5	13	114.82	0	(Kr) 4d(10)5s(2)5p(1)	%E% was discovered in 1863, by Ferdinand Reich, and Heironymous Richter, Freiberg School of Mines, Germany.	1863	It derives its name from the Latin word “indicum“ (“violet” or “indigo”), from the color of the brightest line in its spectrum.	
50	Tin	Sn	5	14	118.71	0	(Kr) 4d(10)5s(2)5p(2)	%E% has been known since antiquity.	-2100	It derives its name from the Anglo-Saxon word “tin“, origin unknown but possibly pre-Indo-European.	Latin: stannum (“tin”), perhaps from Sanskrit: stan (“hard”), or from Indo-European: stagnum or stag (“drip”), since it melts easily.
51	Antimony	Sb	5	15	121.757	0	(Kr) 4d(10)5s(2)5p(3)	%E% has been known since about 3000 BCE.	-1600	It derives its name from the Greek phrase “anti monos“ (“not alone”), taken to mean “not found unalloyed”. Alternately the Greek phrase “anti monachos“ / French: “antimoine“, both meaning “monk-killer”, from antimony's poisonous nature and the fact that most ancient alchemists were monks.	Latin: “stibium“ (mark”), the ancient name for antimony sulfide, or kohl, used as mascara in ancient times.
52	Tellurium	Te	5	16	127.6	0	(Kr) 4d(10)5s(2)5p(4)	%E% was discovered in 1783, by Franz Joseph Müller von Reichenstein, Sibiu, Romania.	1783.1	It derives its name from Tellus, the Latin word for the planet Earth, as well as the name of the goddess of the Earth; to whom, discoverer Müller said, “organized beings owe their existence.”.	
53	Iodine	I	5	17	126.9045	0	(Kr) 4d(10)5s(2)5p(5)	%E% was discovered in 1811, by Bernard Courtois, confirmed by Charles Bernard Desormes and Nicolas Clément.	1811	It derives its name from the Greek word “iodes“ (“violet”).	
54	Xenon	Xe	5	18	131.29	0	(Kr) 4d(10)5s(2)5p(6)	%E% was discovered in 1898, by William Ramsay and Morris William Travers, University College, London.	1898.3	It derives its name from the Greek word “xenos“ (“stranger”), from the arduous process used to first isolate it. Dysprosium (the Greek word “dysprositos“, “hard to get”) was so named for the same reason.	
55	Cesium	Cs	6	1	132.9054	0	(Xe) 6s(1)	%E% was discovered in 1860, by Robert Bunsen and Gustav Kirchoff, Heidelberg, Germany.	1860	It derives its name from the Latin word “caesius“ (“sky blue”), for the color of the flame cesium compounds give when burned.	
56	Barium	Ba	6	2	137.33	0	(Xe) 6s(2)	%E% was discovered in 1808, by Humphry Davy.	1808.4	It derives its name from the Greek word “barys“ (“heavy”), from the weightiness of barium minerals.	
57	Lanthanum	La	6	3	138.9055	0	(Xe) 5d(1)6s(1)	%E% was discovered in 1839, by Carl Gustav Mosander, Karolinska Institute, Stockholm, Sweden.	1839	It derives its name from the Greek word “lanthanein“ (“to lie hidden”), from the fact that it was isolated unexpectedly from a sample of cerium nitrate.	
58	Cerium	Ce	6	3	140.12	0	(Xe) 4f(1)5d(1)6s(2)	%E% was discovered in 1803, by Jöns Jakob Berzelius and Wilhelm Hisinger, in Bastnäs, Sweden; and independently by Martin Heinrich Klaproth in Germany.	1803.5	It was named for the asteroid Ceres, which had been discovered two years earlier.	
59	Praseodymium	Pr	6	3	140.9077	0	(Xe) 4f(3)6s(2)	%E% was discovered in 1885, by Karl Auer, Vienna, Austria, who broke down a sample of didymium into neodymium and praseodymium.	1885.1	It derives its name from the Greek phrase “praseos didymos“ (“green twin”), because it was isolated from didymium, a substance discovered by Carl Gustav Mosander. Mosander mistook the substance for a new element and named it for its similarity to lanthanum, which he discovered at the same time.	
60	Neodymium	Nd	6	3	144.24	0	(Xe) 4f(4)6s(2)	%E% was discovered in 1885, by Karl Auer, Vienna, Austria, who broke down a sample of didymium into neodymium and praseodymium.	1885.2	It derives its name from the Greek phrase “neos didymos“ (“new twin”), because it was isolated from didymium, a substance discovered by Carl Gustav Mosander. Mosander mistook the substance for a new element and named it for its similarity to lanthanum, which he discovered at the same time.	
61	Promethium	Pm	6	3	147	1	(Xe) 4f(5)6s(2)	%E% was first synthesized in 1945, by J.A. Marinsky, L.E. Glendenin, and Charles D. Coryell.	1938	It is named for Prometheus of Greek mythology, who stole fire from the gods and gave it to the human race, from the analogous creation of hitherto unknown elements by physicists.	
62	Samarium	Sm	6	3	150.36	0	(Xe) 4f(6)6s(2)	%E% was discovered in 1879, by Paul-Émile Lecoq de Boisbaudran, Paris, France.	1879.2	It is named for samarskite, the mineral from which it was first isolated, which was in turn named for Vasili Samarsky–Bykhovets, chief of the Russian Mining Engineering Corps.	
63	Europium	Eu	6	3	151.965	0	(Xe) 4f(7)6s(2)	%E% was first isolated in 1901, by Eugène-Anatole Demarçay.	1901	It is named for the continent of Europe.	
64	Gadolinium	Gd	6	3	157.25	0	(Xe) 4f(7)5d(1)6s(2)	%E% was discovered in 1880, by Charles Galissard de Marignac, Geneva, Switzerland.	1880	It was named in honor of Johan Gadolin, who studied the first rare-earth mineral (now called gadolinite).	
65	Terbium	Tb	6	3	158.9253	0	(Xe) 4f(9)6s(2)	%E% was discovered in 1843, by Carl Gustav Mosander, Stockholm, Sweden.	1843	It is one of four elements named for the town of Ytterby, Sweden (The other three are erbium, ytterbium, and yttrium.) Yttrium was discovered near Ytterby; the sample was later found to be impure yttrium oxide, from which the other three elements were eventually isolated.	
66	Dysprosium	Dy	6	3	162.5	0	(Xe) 4f(10)6s(2)	%E% was discovered in 1886, by Paul-Émile Lecoq de Boisbaudran, Paris, France.	1886.3	It derives its name from the Greek word “dysprositos“ (“hard to get”), from the arduous process used to first isolate it. Xenon (the Greek word “xenos“: “stranger”) was so named for the same reason.	
67	Holmium	Ho	6	3	164.9303	0	(Xe) 4f(11)6s(2)	%E% was discovered in 1878, by Marc Delefontaine and Louis Soret, Geneva, Switzerland, and separately by Per Teodor Cleve, Upsalla, Sweden.	1878.1	It derives its name from Holmia, the Latin name for Stockholm, a major source of yttrium oxide, from which holmium was first obtained.	
68	Erbium	Er	6	3	167.26	0	(Xe) 4f(12)6s(2)	%E% was discovered in 1843, by Carl Gustav Mosander, Stockholm, Sweden.	1842	It is one of four elements named for the town of Ytterby, Sweden (The other three are terbium, ytterbium, and yttrium.) Yttrium was discovered near Ytterby; the sample was later found to be impure yttrium oxide, from which the other three elements were eventually isolated.	
69	Thulium	Tm	6	3	168.9342	0	(Xe) 4f(13)6s(2)	%E% was discovered in 1879, by Per Teodor Cleve, University of Uppsala, Sweden.	1879.3	It is named for Thule, the ancient name for Scandinavia, where it was discovered.	
70	Ytterbium	Yb	6	3	173.04	0	(Xe) 4f(14)6s(2)	%E% was discovered in 1878, by Charles Galissard de Marignac, Geneva, Switzerland.	1878.2	It is one of four elements named for the town of Ytterby, Sweden (The other three are erbium, terbium, and yttrium.) Yttrium was discovered near Ytterby; the sample was later found to be impure yttrium oxide, from which the other three elements were eventually isolated.	
71	Lutetium	Lu	6	3	174.967	0	(Xe) 4f(14)5d(1)6s(2)	%E% was discovered in 1907, by Georges Urbain, at the Sorbonne, Paris, France.	1907	It derives its name from Lutetia, the Roman name for Paris, the city where it was discovered.	
72	Hafnium	Hf	6	4	178.49	0	(Xe) 4f(14)5d(2)6s(2)	%E% was discovered in 1923, by George Charles de Hevesy and Dirk Coster, at the University of Copenhagen.	1923	It derives its name from Hafnia, the Latin name for Copenhagen.	
73	Tantalum	Ta	6	5	180.9479	0	(Xe) 4f(14)5d(3)6s(2)	%E% was first isolated in 1903, by Werner von Bolton, Charlottenburg, Germany.	1802	It is named for Tantalus, a figure on Greek mythology said to have stolen the food of the gods and served them a meal of the flesh of his own son; as punishment he was consigned to the underworld to be forever tempted (tantalized) with food and drink which he could never consume. Tantalum and its compounds are largely inert, thereby tantalizing scientists with the difficulty of forming chemical reactions.	
74	Tungsten	W	6	6	183.85	0	(Xe) 4f(14)5d(4)6s(2)	%E% was discovered in 1783, by the brothers Juan Jose and Fausto Elhuyar, Vergara, Spain.	1783.2	It derives its name from the Swedish phrase “tung sten“ (“heavy stone”), an old descriptive name for a calcium tungstate mineral now called scheelite.	For Wolfram, the preferred name for tungsten, as it was the name chosen by its discoverers; from German: “wolf rahm“ (“wolf dirt”), the medieval epithet for tungsten ore, devised by medieval tin miners who found that its presence reduced the amount of tin obtainable from ore, as if it were devouring the tin as a wolf devours sheep.
75	Rhenium	Re	6	7	186.207	0	(Xe) 4f(14)5d(5)6s(2)	%E% was discovered in 1925, by Walter Noddack and Ida Tacke, at the Physico-Technical Testing Laboratory, Berlin, Germany.	1925.1	It derives its name from Rhenus, the Latin name for the Rhine river, after Rhineland, birthplace of discoverer Ida Tacke.	
76	Osmium	Os	6	8	190.2	0	(Xe) 4f(14)5d(6)6s(2)	%E% was discovered in 1803, by Smithson Tennant, in England.	1803.3	It derives its name from the Greek word “osme“ (“smell”), from the pungent osmium tetroxide gas emitted from its surface.	
77	Iridium	Ir	6	9	192.22	0	(Xe) 4f(14)5d(7)6s(2)	%E% was discovered in 1803, by Smithson Tennant, London, England, who discovered osmium at the same time.	1803.4	It is named for Iris, Greek goddess of the rainbow, because of the many colors of its salts.	
78	Platinum	Pt	6	10	195.08	0	(Xe) 4f(14)5d(9)6s(1)	%E% has been known since antiquity.; first identified as an element in 1735, by Spanish astronomer Antonio Ulloa.	1700	It derives its name from the Spanish word “platina“ (“little silver”).	
79	Gold	Au	6	11	196.9665	0	(Xe) 4f(14)5d(10)6s(1)	%E% has been known since antiquity.	-5000	It derives its name from the Anglo-Saxon word “gold“, from “geolo“ (“yellow”).	Latin: aurum (“glow of sunrise”).
80	Mercury	Hg	6	12	200.59	0	(Xe) 4f(14)5d(10)6s(2)	%E% has been known since antiquity.	-1500	It is named for the Greek messenger god Mercury, renowned for his speed and agility, since at room temperature mercury is a quick-flowing silvery liquid.	Latin: hydrargyrum (“liquid silver”).
81	Thallium	Tl	6	13	204.383	0	(Xe) 4f(14)5d(10)6s(2)6p(1)	%E% was discovered in 1861, by William Crookes, Royal College of Science, London, England.	1861.2	It derives its name from the Greek word “thallos“ (“green twig or shoot”), from the green line in its spectrum.	
82	Lead	Pb	6	14	207.2	0	(Xe) 4f(14)5d(10)6s(2)6p(2)	%E% has been known since antiquity.	-1000	It derives its name from the Anglo-Saxon word “lead“; which may derive from the Celtic word “loud“ or the Sanskrit word “loka“ (“reddish”), from lead oxide's red color.	Latin: plumbum (“lead”); possible from Greek: pelios (“bluish-black”), from its color.
83	Bismuth	Bi	6	15	208.9804	0	(Xe) 4f(14)5d(10)6s(2)6p(3)	It is unclear who discovered %e%; it was probably not known in antiquity. It was first identified and named in 1450, by Basileus Valentinus, who called it ‘wismut’.	1500	It derives its name from the German word “bisemutum“, from “wismuth“, a corruption of “weisse masse“ (“white mass”), a description of bismuth oxychloride; or possibly from Arabic “bi ismid“ (“having the properties of antimony”).	
84	Polonium	Po	6	16	210	1	(Xe) 4f(14)5d(10)6s(2)6p(4)	%E% was discovered in 1898, by Marie and Pierre Curie, Paris, France.	1898.4	It is named for Poland, Marie Curie's native country.	
85	Astatine	At	6	17	210	1	(Xe) 4f(14)5d(10)6s(2)6p(5)	%E% was first synthesized in 1940, by Dale R. Corson, K.R. Mackenzie, and Emilio Segré, University of California.	1940.2	It derives its name from the Greek word “astatos“ (“unstable”), from its radioactivity.	
86	Radon	Rn	6	18	222	1	(Xe) 4f(14)5d(10)6s(2)6p(6)	%E% was discovered in 1902, by Ernest Rutherford and Frederick Soddy, McGill University, Canada.	1900	It is named for radium, which emits the gaseous radon from its surface.	
87	Francium	Fr	7	1	223	1	(Rn) 7s(1)	%E% was discovered in 1939, by Marguerite Pery, at the Curie Institute in Paris.	1939	It is named for France, where it was discovered. With gallium, one of two elements named for France.	
88	Radium	Ra	7	2	226.0254	1	(Rn) 7s(2)	%E% was discovered in 1898, by Pierre and Marie Curie, Paris, France.	1898.5	It derives its name from the Latin word “radius“ (“ray”), from the faint blue rays of light it emits as it undergoes radioactive decay.	
89	Actinium	Ac	7	3	227	1	(Rn) 6d(1)7s(2)	%E% was discovered in 1899 by André-Louis Debierne, Paris, France.	1899	It derives its name from the Greek word “actinos“ (“ray”).	
90	Thorium	Th	7	3	232.0381	0	(Rn) 6d(2)7s(2)	%E% was discovered in 1829, by Jöns Jakob Berzelius, Karolinska Institute, Stockholm, Sweden.	1815	It is named for Thor, the Scandinavian god of war.	
91	Protactinium	Pa	7	3	231.0359	1	(Rn) 5f(2)6d(1)7s(2)	%E% was discovered in 1918, by Lise Meitner, Kaiser-Wilhelm Institute for Chemistry, Berlin, Germany.	1917	It derives its name from the Greek prefix “protos“ (“first”) + actinium, so named because protactinium forms actinium as it decays, and is thus a precursor of actinium.	
92	Uranium	U	7	3	238.029	0	(Rn) 5f(3)6d(1)7s(2)	%E% was discovered in 1789, by Martin Heinrich Klaproth, Berlin, Germany.	1789	Klaproth named the new element uran, for the planet Uranus, which has recently been discovered. Uranium in turn determined the names of neptunium and plutonium, the next two elements in the periodic table.	
93	Neptunium	Np	7	3	237.0482	1	(Rn) 5f(4)6d(1)7s(2)	%E% was first synthesized in 1940, by Edwin M. McMillan, with Philip H. Abelson, Berkeley, California.	1940.1	It is named for the planet Neptune, next-furthest planet from the sun after Uranus, since neptunium follows uranium in the periodic table.	
94	Plutonium	Pu	7	3	242	1	(Rn) 5f(6)7s(2)	%E% was first synthesized in 1940, by Glenn T. Seaborg, Arthur C. Wahl, and Joseph W. Kennedy, Berkeley, California.	1940.3	It is named for the planet Pluto, next-furthest planet from the sun after Neptune, since plutonium follows neptunium in the periodic table.	
95	Americium	Am	7	3	243	1	(Rn) 5f(7)7s(2)	%E% was first synthesized in 1944, by Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, and Albert Ghiorso (University of Chicago, Illinois).	1944.2	It is named for the United States of America, where it was first made.	
96	Curium	Cm	7	3	247	1	(Rn) 5f(7)6d(1)7s(2)	%E% was first synthesized in 1944, by Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso, Berkeley, California.	1944.1	It was named in honor of Pierre and Marie Curie.	
97	Berkelium	Bk	7	3	247	1	(Rn) 5f(9)7s(2)	%E% was first synthesized in 1949, by Stanley G. Thompson, Albert Ghiorso, and Glenn T. Seaborg, at the University of California.	1949	It is named for Berkeley, California, where it was first made.	
98	Californium	Cf	7	3	251	1	(Rn) 5f(10)7s(2)	%E% was first synthesized in 1950, by Stanley G. Thompson, Kenneth Street, Jr., Albert Ghiorso, and Glenn T. Seaborg at the University of California.	1950	It was named for California, from the University of California, where it was first made.	
99	Einsteinium	Es	7	3	252	1	(Rn) 5f(11)7s(2)	%E% was first synthesized in 1952, by Albert Ghiorso (University of California) and Gregory R. Choppin (Los Alamos National Laboratory), in the debris generated by the detonation on Eniwetok atoll of the first thermonuclear bomb (codename 'Mike').	1952.1	It was named in honor of Albert Einstein.	
100	Fermium	Fm	7	3	257	1	(Rn) 5f(12)7s(2)	%E% was first synthesized in 1952, by Albert Ghiorso (University of California) and Gregory R. Choppin (Los Alamos National Laboratory), in the debris generated by the detonation on Eniwetok atoll of the first thermonuclear bomb (codename 'Mike').	1952.2	It was named in honor of Enrico Fermi.	
101	Mendelevium	Md	7	3	256	1	(Rn) 5f(13)7s(2)	%E% was first synthesized in 1955 by Albert Ghiorso, Bernard G. Harvey, Gregory R. Choppin, Stanley G. Thompson, and Glenn T. Seaborg, Berkeley, California.	1955	It was named in honor of Dimitri Mendeleyev, creator of one of the first periodic tables in 1869.	
102	Nobelium	No	7	3	259	1	(Rn) 5f(14)7s(2)	%E% was first synthesized in 1956, at the Joint Institute for Nuclear Research, Dubna, USSR.	1956	It was named in honor of Alfred Nobel, Swedish chemist and Nobel Prize founder.	
103	Lawrencium	Lr	7	3	262	1	(Rn) 5f(14)6d(1)7s(2)	%E% was first synthesized in 1961, by Albert Ghiorso and others, at the Lawrence Radiation Laboratories, University of California.	1961	It was named in honor of Ernest O. Lawrence, inventor of the cyclotron.	
104	Rutherfordium	Rf	7	4	261	1	(Rn) 5f(14)6d(2)7s(2)	%E% was first synthesized either in 1964, by Georgy Flerov at the Joint Institute for Nuclear Research in Dubna, USSR; or in 1969, by Albert Ghiorso at the Lawrence Radiation Laboratory, University of California, Berkeley.	1964	It was named in honor of Ernest Rutherford, 1908 Nobel Prize winner.	
105	Dubnium	Db	7	5	262	1	(Rn) 5f(14)6d(3)7s(2)	%E% was first synthesized in 1967, by Georgy Flerov, JINR, Dubna.	1967	It is named for Dubna, USSR, where it was first isolated.	
106	Seaborgium	Sg	7	6	263	1	(Rn) 5f(14)6d(4)7s(2)	%E% was first synthesized in 1974 by Georgy Flerov and Yuri Oganessian at the Joint Institute for Nuclear Research in Dubna, USSR; and by Albert Ghiorso at the University of California, Berkeley.	1974	It was named in honor of Glenn T. Seaborg, synthesizer of many trans-uranium elements.	
107	Bohrium	Bh	7	7	264	1	(Rn) 5f(14)6d(5)7s(2)	%E% was first synthesized in 1976 by Yuri Oganessian at the Joint Institute for Nuclear Research at Dubna, USSR.	1981	It is named for Neils Bohr (originally called neilsbohrium).	
108	Hassium	Hs	7	8	265	1	(Rn) 5f(14)6d(6)7s(2)	%E% was first synthesized in 1984, by Peter Armbruster and Gottfried Münzenberg, at the Institute for Heavy Ion Research in Darmstadt, Germany.	1984	It is named for the German state of Hesse, where it was first synthesized.	
109	Meitnerium	Mt	7	9	268	1	(Rn) 5f(14)6d(7)7s(2)	%E% was first synthesized in 1982, at the Institute for Heavy Ion Research in Darmstadt, Germany.	1982	It is named for Lise Meitner, the Austrian physicist, who discovered protactinium and was the first to propose the concept of nuclear fission.	
110	Ununnilium	Uun	7	10	281	1	(Rn) 5f(14)6d(8)7s(2)		1994		
111	Unununium	Uuu	7	11	272	1	(Rn) 5f(14)6d(9)7s(2)		1994		
112	Ununbium	Uub	7	12	285	1	(Rn) 5f(14)6d(10)7s(2)		1996		
113	Ununtriium	Uut	7	13		1	(Rn) 5f(14)6d(10)7s(2)7p(1)				
114	Ununquadium	Uuq	7	14	289	1	(Rn) 5f(14)6d(10)7s(2)7p(2)		1998		
115	Ununpentium	Uup	7	15		1	(Rn) 5f(14)6d(10)7s(2)7p(3)				
116	Ununhexium	Uuh	7	16	292	1	(Rn) 5f(14)6d(10)7s(2)7p(4)		1999