Chemical Elements, actinium to bromine,
Chart 1 of 8

actinium | aluminum | americium | antimony | argon | arsenic | astatine | barium | berkelium | beryllium | bismuth | bohrium | boron | bromine

This is the first of eight groups of chem elements available in this cross-reference searches.

The Chemical Elements Chart is here.

The Chemical-Elements Table Index is here.

actinium (Modern Latin: chemical element; from Greek, aktis, aktinos ray; radioactive metal).
Symbol: Ac
Atomic number: 89
Year discovered: 1899
Discovered by: French chemist André-Louis Debierne (1874-1949), and independently by F. O. Giesel, in 1902, both of whom obtained it while working on “separation techniques” for rare earth oxides.

Additional information:
  • There was more in uranium ores than the polonium and radium that the Curies had detected (see polonium).
  • Debierne, a close friend of the Curies, isolated still another element from the ores which he called “actinium”, from a Greek word for “ray”, so that the name was the Greek equivalent of the Latin “radium.”
  • In the past, actinium was of interest only as a scientific study; however, it is now being considered as a source of heat in space vehicles.
  • actinometer, the general name for any instrument used to measure the intensity of radiant energy.
  • actinomycosis, an infectious disease caused by Gram-positive bacteria with a characteristic filamentous branching shape which are known as actinomycetes.
Name in other languages:
French: actinium
German: Actinium
Italian: attinio
Spanish: actinio

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aluminum or aluminium (Modern Latin: chemical element; from Greek and Latin, alumen, a substance having an astringent taste; metal).
Symbol: Al
Atomic number: 13
Year discovered: 1825
Discovered by: Hans Christian Oersted (1777-1851), a Danish physicist; and coined in 1812 by the British chemist Sir Humphry Davy (1778-1829).

Additional information:
  • Crude aluminum was isolated (1825) by Hans Christian Oersted by reducing aluminum chloride with potassium amalgam.
  • Sir Humphry Davy had prepared (1809) an iron-aluminum alloy by electrolyzing fused alumina (aluminum oxide) and had already named the element aluminum; the word later was modified to aluminium in England and some other European countries.
  • A German chemist, Friedrich Wöhler, using potassium metal as the reducing agent, produced aluminum powder (1827) and small globules of the metal (1845) from which he was able to determine some of its properties.
  • Aluminum, or aluminium, is the most modern of the common metals, having been first introduced to the public in 1825 at the Paris exposition.
  • When electric power became relatively plentiful and less expensive, almost simultaneously Charles Martin Hall (1863-1914) in the United States and Paul-Louis-Toussaint Héroult (1863-1914) in France discovered (1886) the modern method of commercially producing aluminum: electrolysis of purified alumina dissolved in molten cryolite.
  • In his home laboratory, using homemade batteries, Hall devised a method of preparing aluminum by the use of an electric current, just as Davy had prepared sodium and potassium nearly eighty years before (1807).
  • He used aluminum oxide dissolved in a molten mineral named cryolite, and into it he stuck carbon electrodes.
  • Oddly enough, that same year a French metallurgist, Paul-Louis-Toussaint Héroult, with the same last initial and the same birth and death years, independently devised precisely the same system, which is called the “Hall-Héroult process”.
  • Aluminum became less expensive almost immediately, and it is now second only to steel as a structural material.
  • For example, a combination of lightness and strength makes it ideal for aircraft.
  • Pure aluminum (99.996 percent) is quite soft and weak; commercial aluminum (99.0 to 99.6 percent pure) with small amounts of silicon and iron is hard and strong.
  • Ductile and highly malleable, aluminum can be drawn into wire or rolled into thin foil.
  • The metal is only about one-third as dense as iron or copper.
  • Though chemically active, aluminum is nevertheless highly corrosion-resistant because in air a hard, tough, oxide film forms on its surface.
  • As a result of its relative cost, aluminum is used widely for food-processing equipment, food containers, food-packaging foils, and numerous vessels for the processing of chemicals.
  • Because of its good electrical conductivity (exceeded only by gold, silver, and copper), aluminum is used as an electrical conductor, particularly for high-voltage transmission lines.
  • Aluminum alloys readily with copper, manganese, magnesium, silicon, and zinc.
  • The ancient Greeks and Romans used alum in medicine as an astringent and in dyeing processes.
  • In 1761 de Morveau proposed the name “alumine” for the base in alum. In 1807, Davy proposed the name alumium for the metal, undiscovered at that time, and later agreed to change it to aluminum.
  • Shortly thereafter, the name aluminium [note extra “i”) was adopted by IUPAC (International Union of Pure and Applied Chemistry) to conform with the “-ium” ending of most elements.
  • Aluminium is the IUPAC (International Union of Pure and Applied Chemistry) spelling and therefore the international standard (with the extra “i” in the last syllable).
  • Aluminium was also the accepted spelling in the U.S.A. until 1925, at which time the American Chemical Society (ACS) decided to revert back to aluminum, and to this day Americans still refer to aluminium as “aluminum” while just about everyone else in the world spell it “aluminium” [al" yoo MIN ee uhm].
Name in other languages:
British: aluminium
French: aluminium
German: Aluminium
Italian: alluminio
Spanish: aluminio

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americium (Modern Latin: chemical element; a form of America; radioactive metal).
Symbol: Am
Atomic number: 95
Year discovered: 1944
Discovered by: Glenn Theodore Seaborg (1912-1999), American physicist; and co-workers, Albert Ghiorso (born July 15, 1915), Ralph A. James, and Leon O. Morgan at the war-time Metallurgical Laboratory of The University of Chicago.

Additional information:
  • Seaborg, and his co-workers, suggested the name americium, after the Americas; since its rare-earth homologue, europium, had been named for Europe.
  • It is used as the starting material for the production of curium, which is used in isotope power sources.
Name in other languages:
French: américium
German: Americium
Italian: americio
Spanish: americio

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antimony (Greek: chemical element; antimonos, opposed to solitude; symbol Sb is from Latin stibium [powdered antimony]; some say antimony means, “a metal seldom found alone”; metal).
Symbol: Sb
Atomic number: 51
Year discovered: c. 900
Discovered by: Some say Rahazes [Razi Abu Bakr Muhammad ibn Zakariya], c. 865, a Persian physician; while others give credit to Basil Valentine, a 15th century German monk.

Additional information:
  • Rhazes was a Persian physician and philosopher who was considered the greatest physician of the Islamic world.
  • He was the chief physician at hospitals in Rayy and Baghdad; and believed in the atomist theory of nature.
  • Some of his words were translated into Latin and he had a great influence on medical science in the Middle Ages.
  • Basil Valentine was an enthusiastic investigator of the properties of antimony and he noted the ability of antimony to free gold from its impurities and concluded it had a similar effect on man.
  • According to this belief, cattle were often fed antimony to fatten them.
  • Monks reportedly used the same method to avoid the effects of fasting, often being fatally poisoned.
  • Some speculators, therefore, attribute the name “antimony” to the combination of the Greek anti, “against,” and monos, “one who dwells alone”; that is, a monk.
  • A more accurate interpretation suggested by a lexicographer is antimonos, “a metal seldom found alone.”
  • In St. Jerome’s translation of the Bible, Jezebel, the wicked wife of Ahab, is reported to have painted her eyes with stibium, a name that has given antimony its chemical symbol, Sb.
  • Egyptian women used cosmetics made of antimony to beautify their faces and water from Egyptian wells was often borne in antimony vessels.
  • This metal is easy to pulverize.
  • Of the more common metals, antimony is the poorest conductor.
  • It is used in alloys, with lead for storage battery plates, with lead and tin in type metals and body solders, and with tin and copper in bearing or antifriction metals.
  • Its many peculiar characteristics make it valuable as a component of flameproofing chemicals, ceramic enamels, compound semiconductors, smoke generators, explosives, and medicines.
Name in other languages:
French: antimoine
German: Antimon
Italian: antimonio
Spanish: antimonio

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argon (Greek: argus, neutral, inactive, idle, inert; gas).
Symbol: Ar
Atomic number: 18
Year discovered: 1894
Discovered by: Sir William Ramsay (1852-1916), a British chemist; and John William Strutt, Lord Rayleigh (1842-1919), a British physicist.

Additional information:
  • Rayleigh was trying to measure the atomic weight of nitrogen when he encountered an unexplainable result.
  • Whereas oxygen always had the same atomic weight no matter how it was prepared, nitrogen did not.
  • Nitrogen prepared from the atmosphere consistently showed a slightly higher atomic weight than nitrogen prepared from a variety of nitrogen-containing compounds.
  • Rayleigh could not find a suitable explanation for this and so he wrote a letter to the journal Nature, asking for suggestions.
  • British chemist William Ramsay accepted the challenge.
  • Ramsay repeated an experiment made by British chemist Henry Cavendish (back in 1766) who had tried to combine the nitrogen of air with oxygen and had found that a small bubble of gas remained behind, which would simply not combine with oxygen.
  • Cavendish apparently thought there might be some small quantity of gas in the atmosphere that was more dense than nitrogen, and more inert, too, but he did not pursue the matter.
  • Ramsay had access to spectroscopic techniques that Cavendish did not have.
  • He heated the bubble of gas, studied the spectral lines it emitted, and found them to be in positions that did not fit any known element.
  • It seemed obvious that there was an unknown gaseous element, that made up about one percent of the atmosphere.
  • It was completely inert and would not react with any substance; and it was also much more dense than nitrogen.
  • The presence of this new gas as an impurity in the nitrogen obtained from air gave it an abnormally high atomic weight, whereas nitrogen obtained from chemicals without any mixture of this impurity gave the true atomic weight.
  • The discovery was announced on August 13, 1894, and the new gas was named “argon”, from the Greek word for “inert”.
  • As a result, Rayleigh received the Nobel Prize in physics and Ramsay the Nobel Prize in chemistry in 1904.
  • It was isolated by examination of the residue obtained by removing nitrogen, oxygen, carbon dioxide, and water from clean air.
  • In fact, air contains less than one percent argon.
  • It was recognized by the characteristic lines in the red end of the spectrum.
  • Argon was the first of the noble gases to be isolated from a terrestrial source.
  • Helium was detected in the sun in 1868.
Name in other languages:
French: argon
German: Argon
Italian: argo
Spanish: argón

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arsenic (Latin: arsenicum, yellow; gold, golden; nonmetal).
Symbol: As
Atomic number: 33
Year discovered: 1250
Discovered by: Possibly first separated by Albertus Magnus (c.1193-1280), the 13th century German scholastic philosopher.

Additional information:
  • Elemental arsenic may have been first recorded by the Greek historian Zosimus in the 5th century A.D.
  • Pedanios Dioscorides and Pliny the Elder in the 1st century refer to auripigmentum, which was probably orpiment.
  • Both observed the change in color and properties of the sulfide on calcining it.
  • Some believe that Albertus Magnus, was the first to isolate and identify arsenic as an element.
  • He noted the appearance of a metal-like substance on heating arsenicum (arsenious sulfide) with soap.
  • Arsenic and its compounds are used in insecticides, weed killers, solid-state doping agents, and various alloys.
  • Arsenic compounds were mined by the early Chinese, Greek and Egyptian civilizations.
  • No doubt they discovered its toxic properties early.
  • It is believed that Albertus Magnus obtained the element in 1250 A.D. and obtained it by heating soap together with orpiment (arsenic trisulphide).
  • Arsenic causes acute inflammation of the stomach and also affects other parts of the body.
  • Its compounds have been used in medicines at least since the time of Hippocrates in the 5th century B.C.
Name in other languages:
French: arsenic
German: Arsen
Italian: arsenico
Spanish: arsénico

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Symbol: At
Atomic number: 85
Year discovered: 1940; named in 1947 at the University of California, Berkeley.
Discovered by: Emilio Gino Segrè (1905-1989), Italian physicist, Dale R. Corson, and Kenneth R. MacKenzie.

Additional information:
  • Astatine was synthesized in 1940 by Dale Corson, Kenneth MacKenzie, and Emilio Segrè at the University of California, Berkeley, by bombarding bismuth with alpha-particles which resulted in a nuclear reaction.
  • Astatine has some physiological importance because it is readily taken up by the thyroid gland as is iodine.
  • In general, it resembles iodine.
Name in other languages:
French: astate
German: Astat
Italian: astato
Spanish: astato

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Symbol: Ba
Atomic number: 56
Year discovered: 1808
Discovered by: Sir Humphry Davy (1778-1829), an English chemist.

Additional information:
  • Barium oxidizes very rapidly in air, and reacts readily with water and alcohol.
  • It was first investigated in 1602 by Vincenzo Cascariolo, a shoemaker of Bologna, who found that after ignition with combustible substances, it became phosphorescent, and on this account it was frequently called Bolognian phosphorus.
  • In 1774, K. W. Scheele, in examining a specimen of pyrolusite, found a new substance to be present in the mineral, for on treatment with sulfuric acid it gave an insoluble salt which was afterward shown to be identical with that contained in heavy spar.
  • The metal is difficult to isolate; Sir Humphry Davy tried to electrolyze baryta (barium oxide) but was unsuccessful; later attempts were made by using barium chloride in the presence of mercury.
  • In this way he obtained an amalgam, from which on distilling off the mercury the barium was obtained as a silver white residue.
  • Barium was first isolated by Davy in 1808.
  • It is used in the manufacture of radio vacuum tubes because it removes the final traces of gaseous elements that remain after the tubes have been evacuated almost completely by other methods.
Name in other languages:
French: baryum
German: Barium
Italian: bario
Spanish: bario

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Symbol: Bk
Atomic number: 97
Year discovered: 1949
Discovered by: Glenn Theodore Seaborg (1912-1999), American physicist; and co-workers, Albert Ghiorso (born July 15, 1915), and S. G. Thompson at the University of California at Berkeley.

Additional information:
  • The scientists suggested the name berkelium in honor of the place of its discovery.
  • It was first isolated in weighable amounts by Thompson and B. B. Cunningham at Berkeley in 1958.
  • Berkelium is a man-made chemical element that exists only in radioactive forms prepared by nuclear reaction.
Name in other languages:
French: berkélium
German: Berkelium
Italian: berkelio
Spanish: berkelio

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Symbol: Be
Atomic number: 4
Year discovered: 1798
Discovered by: Nicolas Louis Vauquelin (1763-1829), a French chemist.

Additional information:
  • Emeralds and beryl were both known to early Egyptians but it was not realized until the end of the 18th century that they are the same mineral, now called beryllium aluminum (aluminium) silicate.
  • The element was recognized by Nicolas Louis Vauquelin in 1798 in beryl and emeralds.
  • The metal was isolated much later in 1828 by Friederich Wöhler and independently by A. B. Bussy.
  • The low atomic weight of beryllium makes it useful for windows of X-ray tubes because they readily pass through them.
  • Date line, March 30, 1999- DEADLY DUST? A published report claims a material used to make U.S. defense equipment is giving workers a deadly lung disease. The rare metal beryllium is lighter than aluminum and more rigid than steel, but The Toledo Blade (Ohio) says a 22-month investigation found about 1,200 Americans have contracted a potentially fatal lung disease and hundreds have died after inhaling the metal’s dust. From the United Press International (UPI).
Name in other languages:
French: beryllium
German: Beryllium
Italian: berillio
Spanish: berilio

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Symbol: Bi
Atomic number: 83
Year discovered: no data
Discovered by: Discovered by:Known since ancient times.

Additional information:
  • In early times bismuth was confused with tin and lead.
  • Georgius Agricola, the mining and metallurgy historian, in the 16th century regarded bismuth as a true metal and distinct from metals such as tin, lead, and antimony.
  • German, Bismut (now also spelled Wismut) was Latinized by Georgius Agricola in 1530 as bisemutum.
  • Claude J. Geoffroy, the Younger, showed it to be distinct from lead in 1753.
  • Because of their low melting points, bismuth eutectic alloys are used in automatic sprinkler systems, fuse and safety plugs, and in automatic fire-alarm systems.
Name in other languages:
French: bismuth
German: Bismut or Wismut
Italian: bismuto
Spanish: bismuto

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Symbol: Bh
Atomic number: 107
Year discovered: 1981
Discovered by: Peter Armbruster, Gottfried Münzenberg, and their co-workers; at Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany.

Additional information:
  • Niels Bohr used to begin his lectures by saying to his students, “Every sentence that I utter should be regarded by you not as an assertion but as a question.”.
  • Scientists from the USSR reported their production of an isotope of bohrium in 1976 and this work was substantiated later by German scientists..
  • This element was named in honor of Niels Henrik David Bohr, a Danish physicist, considered one of the foremost scientists of the 20th century.
  • It was previously named unnilseptium (Uns) which is the Latin equivalent of atomic number “107”.
Name in other languages:
French: bohrium
German: Bohrium
Italian: bohrio
Spanish: bohrio

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Symbol: B
Atomic number: 5
Year discovered: 1808
Discovered by: Joseph Louis Gay-Lussac (1778-1850), French chemist and physicist; Louis-Jacques Thénard (1777-1857), French chemist; and Sir Humphry Davy (1778-1829), English chemist.

Additional information:
  • Discovered in France and England. Boron compounds have been known for thousands of years, but the element was not isolated until 1808 by Sir Humphry Davy, Joseph-Louis Gay-Lussac, and Louis Jaques Thénard.
  • This was accomplished through the reaction of boric acid with potassium.
  • It was originally called “boracium” by English chemist, Sir Humphry Davy, because it was drawn from boracic (boric) acid.
  • Boron filaments are used with plastics or metals as reinforcements to form composites that are superior in strength and stiffness of either of the other materials in composite.
Name in other languages:
French: bore
German: Bor
Italian: boro
Spanish: boro

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Symbol: Br
Atomic number: 35
Year discovered: 1825 -1826
Discovered by: Antoine Jélrôme Balard (1802-1876), a French chemist.

Additional information:
  • While working with seaweed, Balard found that at times he obtained a brown substance in solution in the liquid he was using to dissolve the ashes of the seaweed.
  • In 1826, he tracked this color to a substance that had properties apparently just midway between those of chlorine and iodine.
  • For a while he thought he had a compound of those two elements, but further investigation convinced him he had a new element.
  • Bromine is corrosive to metals, irritating to the skin, and as a result of its unpleasant odor, it was given the name bromine (Greek, bromos, “stench”).
  • It is also known as a heavy, volatile, nonmetallic liquid element that has a highly irritating vapor.
  • Traditionally obtained from salt deposits, the element is now produced in commercial quantities by the processing of ocean water.
  • The most important use of bromine is in the manufacture of ethylene bromide, one ingredient of “antiknock” fluid for motor fuels.
  • Other major uses of bromine are in the manufacture of methyl bromide, a fumigant employed for insect control in the food industries, and of various dyes, particularly the bromo-indigos.
Name in other languages:
French: brome
German: Brom
Italian: bromo
Spanish: bromo

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