alloy A material that has metallic properties and is composed of two or more chemical elements of which at least one is a metal. Alloys are usually harder than pure metal and more resistant to corrosion. Brass is an alloy made from 70 per cent copper and 30 per cent zinc; bronze is an alloy of 90 per cent copper and 10 per cent tin.
amalgam An alloy of mercury with another metal. Iron does not form an amalgam with mercury but most other metals do. Dental amalgam, combining mercury with silver, tin and other metals, was popular from around 1800 onwards, but is less used today because of health concerns over the use of mercury.
ductile Capable of being pulled out into a wire.
heavy metal One of a group of elements among transition metals, metalloids, lanthanides and actinides that have metallic properties. The term generally refers to those that are heavier than iron and zinc. Examples include mercury, lead and cadmium. They are toxic to humans if ingested.
insulator Material that prevents an electrical charge flowing through it.
isomers Compounds with an identical molecular formula but different structural formulae. While a molecular formula describes the combination of elements in a molecular compound, the structural formula describes how the atoms are fitted together in the molecule. For example, isomers of hydrocarbons have the same number of hydrogen and carbon atoms, but they are connected in different ways.
metastable state A relatively stable state of an atom or molecule, more stable than its most excited states, but less stable than its most stable state.
nuclear isomer A metastable state of an atomic nucleus, in which one or more of its protons or neutrons is excited (has an elevated level of energy).
ore Rock containing a valuable element (typically a metal), for which it is mined.
photon A quantum (bundle) of electromagnetic energy.
quadruple bond Bond between two atoms that involves eight bonding electrons. A single bond involves two electrons, a double bond four and a triple bond six. Quadruple bonds are most commonly made among transition metals such as rhenium and chromium.
salts Ionic compounds formed when an acid undergoes a neutralization reaction with a base.
superheavy element Another name for transuranic elements (see here), elements with an atomic number greater than 92 (the atomic number of uranium). In some contexts, however, superheavy element refers to elements with an atomic number greater than 100.
TRANSITION METALS
The transition metals are in groups 3–12 of the periodic table. They are mostly dense and hard, and are good conductors of electricity and heat. Their valence electrons (with which they combine with other elements) are in more than one electron shell.
Transition metals
|
Symbol |
Atomic Number |
Scandium |
Sc |
21 |
Titanium |
Ti |
22 |
Vanadium |
V |
23 |
Chromium |
Cr |
24 |
Manganese |
Mn |
25 |
Iron |
Fe |
26 |
Cobalt |
Co |
27 |
Nickel |
Ni |
28 |
Copper |
Cu |
29 |
Zinc |
Zn |
30 |
Yttrium |
Y |
39 |
Zirconium |
Zr |
40 |
Niobium |
Nb |
41 |
Molybdenum |
Mo |
42 |
Technetium |
Tc |
43 |
Ruthenium |
Ru |
44 |
Rhodium |
Rh |
45 |
Palladium |
Pd |
46 |
Silver |
Ag |
47 |
Cadmium |
Cd |
48 |
Lutetium |
Lu |
71 |
Hafnium |
Hf |
72 |
Tantalum |
Ta |
73 |
Tungsten |
W |
74 |
Rhenium |
Re |
75 |
Osmium |
Os |
76 |
Iridium |
Ir |
77 |
Platinum |
Pt |
78 |
Gold |
Au |
79 |
Mercury |
Hg |
80 |
Lawrencium |
Lr |
103 |
Rutherfordium |
Rf |
104 |
Dubnium |
Db |
105 |
Seaborgium |
Sg |
106 |
Bohrium |
Bh |
107 |
Hassium |
Hs |
108 |
Meitnerium |
Mt |
109 |
Darmstadtium |
Ds |
110 |
Roentgenium |
Rg |
111 |
Copernicium |
Cn |
112 |
Chromium is one of the so-called transition metals (like iron, cobalt, nickel and copper). Its compounds form the basis of many traditional artists’ pigments and paints; chrome yellow, for example, is pure lead chromate. The colour of rubies and emeralds is due to contamination of otherwise transparent crystalline material with small amounts of chromium oxide. Chromium was discovered in 1798 by French chemist Louis-Nicolas Vauquelin, who ground up precious stones in an effort to explain their colours, and later discovered the element beryllium in the same way. Chromium alloyed with iron makes stainless steel, which does not oxidize or rust. Stainless steel in cutlery might contain as much as 18 per cent chromium, while that for marine use may contain even more. However, it is in the form of chrome plating that we know the element best. This process only became possible on a wide scale with the commercialization of electroplating in the 1920s. ‘Chrome’ was adopted as a symbol of the consumer society. In 1933, American etiquette expert Emily Post hailed it as the ‘answer to the housewife’s prayer’. More recently, though, it seems that the familiar thin layer of chrome has come to denote a merely superficial glamour.
3-SECOND STATE
Chemical symbol: Cr
Atomic number: 24
Named: From Greek chroma (‘colour’)
3-MINUTE REACTION
Solutions of chromium sulphate have been used since the mid-19th century in the tanning of leather to make it water resistant. The chemistry of the interaction between the inorganic chromium complexes and the organic collagen in the leather is highly involved. Human exposure to these chromate salts can lead to ulcers, and tanneries have released the salts into rivers. Other chromium compounds are still more hazardous, increasing environmental concerns.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
COLIN G. FINK
1881–1953
American chemist who perfected chrome plating at Columbia University
HARLEY EARL
1893–1969
American industrial designer, the ‘da Vinci of Detroit’, responsible for extravagant chrome styling on cars
30-SECOND TEXT
Hugh Aldersey-Williams
Chromium’s many oxidation states lead to compounds with a wide range of colours admired by artists, but we are most familiar with this element through the use of chrome plating.
As iron ore (oxide) and other minerals, iron makes up about 5 per cent of the earth’s crust, and is the fourth most abundant element there. The earth’s core is mostly iron, molten in the outer core and solid in the middle; the sloshing of magnetic liquid iron creates the geomagnetic field, which helps protect life from the solar wind. Iron in haemoglobin makes blood red and ferries oxygen. The importance of iron can be judged from the use of the phrase ‘Iron Age’ to describe a period of human history (beginning in the Middle East in about 1500 BCE): the Hittites, early iron smelters, trampled over Asia Minor, just as the iron-clad Romans later conquered half the world. Swords made in the earlier Bronze Age didn’t stand a chance against hard, gleaming steel. Steel is iron mixed with a little carbon, which makes it harder. Because charcoal is used to extract iron from its ore, what you get is inevitably steel instead of pure, softer iron. The best steel requires precise control of carbon content, which became possible in the mid-19th century; only then could engineers build steel bridges without fear that the structures would crack.
3-SECOND STATE
Chemical symbol: Fe
Atomic number: 26
Named: From Anglo-Saxon iren; Fe from Latin ferrum
3-MINUTE REACTION
Of all elements, iron has the most stable nucleus, prone neither to nuclear fusion (merging) or fission (splitting). Crudely put, this stability comes from an ideal balance of constituents. With fewer nuclear particles (protons and neutrons), the nucleus has too much surface, prompting droplet-like mergers; with more protons, there’s too much electrical repulsion. So nuclear fusion in stars stops when the constituents are converted to iron.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
TOBERN BERGMANN
1735–84
Swedish chemist who established how carbon dictates the properties of steel
HENRY BESSEMER
1813–98
British engineer who invented modern steel-making
30-SECOND TEXT
Philip Ball
Iron colours the surface of Mars, the ‘red planet’, and gives its name to Ironbridge Gorge in Shropshire, England, where a 30-m (100-foot)-span iron bridge was built in 1779–81.
Familiar, reddish-orange copper is not considered a precious metal, but it is precious enough to those who strip it from unwatched buildings. An unusually good conductor of both heat and electricity, copper is widely used for sheets, wires, pipes and fittings. Found naturally in the free state, copper occurs combined in many minerals, usually in association with sulphur. It is harder than zinc but softer than iron, and acquires strength and structure by mixing with other metals in more than 1,000 combinations. Combined with 10 per cent tin, it forms the alloy bronze, which gave its name to an age of human development three millennia long (roughly 3600 BCE—600 BCE), when weapons and implements were chiefly made of copper and bronze. Freshly exposed copper has street appeal, ages gracefully to an earthy mahogany and, with weather, becomes robed – like the Statue of Liberty in New York City – in a patina of verdigris. Its compounds, commonly encountered as copper(II) salts, often produce blue or green colours in such minerals as turquoise and malachite. The element is present in minute amounts in the animal body, and is essential to normal metabolism.
3-SECOND STATE
Chemical symbol: Cu
Atomic number: 29
Named: From cypriumaes, the latin for ‘Cyprus metal’ – Cyprus was the chief source of copper in Roman times
3-MINUTE REACTION
Natural copper is a mixture of two stable isotopes: Cu-63 (69.17 per cent) and Cu-65 (30.83 per cent). Copper has low chemical reactivity and resists corrosion, forming a layer of brown-black copper oxide, and, eventually, a green layer of copper carbonate. Like silver and gold, copper’s fellows in group 11, its atoms form relatively weak metallic bonds, rendering these metals extremely malleable and ductile and imparting exceptionally good thermal and electrical conductivity.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
FRÉDÉRIC BARTHOLDI
1834–1904
French designer responsible for the Statue of Liberty
WILLIAM A. CLARK, MARCUS DALY & F. AUGUSTUS HEINZE, KNOWN AS ‘THE COPPER KINGS OF MONTANA’
Fl. late 19th century
American entrepreneurs who fought over Montana’s copper-mining industry
30-SECOND TEXT
Jeffrey Owen Moran
The Statue of Liberty, erected in 1886, has a copper exterior and was originally a copper colour, but it developed a green ‘patina’ as the copper oxidized in the years after 1900.
Technetium, or element 43, was first synthesized in 1937. The experiments took place in Berkeley, California, but the new element’s discovery had to wait until plates of irradiated molybdenum had been sent to Sicily. There, Italian physicist Emilio Segrè, who had recently returned home after working in Berkeley, and a chemist colleague, Carlo Perrier, discovered that element 43 had been created as a result of irradiation – the first artificially synthesized element. Technetium was later found to occur naturally on the earth but only in minuscule amounts. Its rarity is surprising given its relatively low atomic number of 43; the full explanation is complicated, but it is connected with the fact that its isotopes contain odd numbers of protons and also neutrons. Among many other applications, technetium is used in hospitals in medical imaging. This involves one isotope of the element, Tc-99, and a metastable nuclear isomer of this isotope. What makes this isotope especially useful is that it has a half-life of about six hours. This means that over a period of 24 hours about 94 per cent of the technetium isotope decays from the body.
3-SECOND STATE
Chemical symbol: Tc
Atomic number: 43
Named: From Greek technos (‘artificial’)
3-MINUTE REACTION
German chemists Ida and Walter Noddack claimed to have discovered element 43 in 1925, calling it ‘masurium’, and as recently as the turn of the 21st century, two physicists – the Belgian Pieter van Assche and the American John T. Armstrong – were still claiming that the Noddacks had, in fact, isolated element 43 in 1925. This claim has now finally been refuted by a number of other authors.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
WALTER NODDACK & IDA NODDACK
1893–1960 & 1896–1978
German chemists who claimed to have discovered element 43 in Berlin in 1925
CARLO PERRIER & EMILIO SEGRÈ
1886–1948 & 1905–89
Italian physicist and chemist who were the true co-discoverers of element 43 in Palermo in 1937
30-SECOND TEXT
Eric Scerri
The technetium isotope, Tc-99, is used in around 50 million medical imaging procedures carried out each year and has also been proposed for use in nuclear batteries.
By the 1920s, a handful of elusive elements remained to be discovered on Dmitri Mendeleev’s periodic table. Given the radioactive nature of these elements – and more that Mendeleev did not predict – it was time for physicists to step forward in the search. Nobel Prize winner Emilio Segrè was a pioneering atomic and nuclear physicist who discovered artificially created elements that could not be found on the earth.
Born in 1905, Segrè grew up in Tivoli and studied physics at the University of Rome. He completed his doctorate in 1928 under the supervision of Enrico Fermi, one of the leading nuclear physicists of the 20th century. During the 1930s, Segrè was part of Fermi’s young team at the University of Rome that became famous for groundbreaking discoveries in neutron bombardment, in particular the production of slow neutrons that would later be used to trigger nuclear fission reactions.
In 1936, Segrè was appointed director of physics at the University of Palermo, where he used his experience in Rome effectively. Scientists knew that there was a ‘missing’ element in the periodic table under manganese and set out to predict its properties. However, element 43 proved difficult to find.
In 1937, at the University of California, Berkeley, scientists sent Segrè and mineralogist Carlo Perrier a strip of molybdenum that had been bombarded with deuterons in a cyclotron and was producing anomalous radioactivity. Segrè proved that the radiation emitted was produced by technetium, and he entered the record books by identifying it as the first artificially synthesized chemical element. Technetium has a half-life of 4 million years, so any produced when the planet was formed 4.57 billion years ago would be long gone.
Segrè was Jewish and on a research trip to California in 1938 was dismissed from his post at Palermo by Benito Mussolini’s fascist government. Working at Berkeley during wartime, he helped to discover the element astatine and the isotope plutonium-239, which was fissionable. In 1943, Segrè became a group leader in the Manhattan Project, developing the atomic bomb that used plutonium-239 with such deadly consequences on Nagasaki, Japan, on 9 August 1945.
Segrè became a US citizen and taught at Berkeley until 1972. Working with the American physicist Owen Chamberlain, he discovered the antiproton (a subatomic antiparticle) and the duo shared the Nobel Prize for Physics in 1959 for their achievement.
Born in Tivoli, near Rome
1922
Attends University of Rome, studying first engineering then physics
1928
Achieves physics doctorate supervised by Enrico Fermi
1928
Serves a year in the Italian army
1932
Appointed assistant professor at the University of Rome
1936
Becomes director of the physics laboratory at the University of Palermo
1937
Isolates the element technetium
1938
Dismissed from his post under anti-semitic laws in Italy
1940
Isolates the element astatine. Discovers plutonium-239 is fissionable
1943–46
Appointed a group leader in the Manhattan Project at Los Alamos National Laboratory
1959
Wins Nobel Prize for Physics
1972
Returns to Rome from United States as a professor of nuclear physics
22 April 1989
Dies of a heart attack
Among metals, silver stands supreme in three ways: it is the best conductor of electricity, it is the best conductor of heat and it gives the best reflectance (a technical measure of how well a surface reflects). These features are exploited commercially in grinding wheels, electronics and mirrors. Silver solder is used to attach industrial diamonds to grinding wheels, because it dissipates the heat generated more effectively. Silver is widely used for electrical and electronic devices, because it makes and breaks electric circuits cleanly, and, in addition to mirrors, is used for trophies and special tableware. The chief silver ore is acanthite (silver sulphide), but most silver is obtained as a by-product in the refining of copper and lead. Silver salts are sensitive to light and were an essential part of photographic film. Now they feature in reactive sunglasses. Sunlight converts colourless silver ions (Ag+) to metallic silver by taking an electron from a copper atom, and the glass darkens; when the light fades, the electron returns to the copper. Silver is deadly to bacteria and viruses, and silver nitrate used to be applied to wounds as an antiseptic. It is now added to paints to keep surfaces free of disease pathogens.
3-SECOND STATE
Chemical symbol: Ag
Atomic number: 47
Named: From Anglo Saxon siolfur; Ag from Latin argentum
3-MINUTE REACTION
Silver is a member of group 11 of the periodic table, the coinage metals. It is stable to oxygen and water, but dissolves in sulphuric and nitric acids. The metal is slowly attacked by sulphur compounds in the air that form black silver sulphide. Silver nitrate was known to the ancients as lunar caustic. This salt was remarkably soluble in water and much used as a caustic; silver chloride – completely insoluble – was used in precipitating silver.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
JOSEPH NICÉPHORE NIÉPCE
1765–1833
French inventor who took the first ever photograph in 1816, using silver chloride
JOHN WRIGHT
1808–44
British doctor who discovered how to silver plate other metals, in 1840
CARL FRANZ CREDÉ
1819–92
German gynaecologist who introduced silver nitrate drops in 1884 to kill a virus in babies
30-SECOND TEXT
John Emsley
Silver would take gold medal in a competition for the best conductor and reflector. Unless you’re an Olympic athlete, you’re perhaps most likely to handle it in silver-plated cutlery.
Hafnium is a silvery, ductile metal with corrosion-resistant properties. A remarkable aspect of element 72 is the number of the priority disputes over its discovery. One of the first scientists who believed he had discovered the element was French inorganic chemist Georges Urbain, in 1911. Then English physicist Henry Moseley established an X-ray method that provided a definitive way of checking the atomic number of any particular element and showed that Urbain had not isolated element 72. A few years later, however, Urbain revived his claim and was supported by the popular press, especially in France and Britain. This was shortly after the First World War, when rivalries were strong between England and France on one side and the Germanic nations on the other; Denmark was not strictly a Germanic nation, and neither of the two scientists, Dutchman Dirk Coster and Hungarian George de Hevesy, who discovered hafnium in Denmark, were Danish. Nevertheless, they were subjected to press criticism and ridicule until they produced X-ray evidence. They were eventually declared discoverers of the new element. It is used to make control rods for nuclear reactors and is present in many high-tech alloys used in the space and computer industries.
THE 3-SECOND STATE
Chemical symbol: Hf
Atomic number: 72
Named: From Hafnia, the Latin name for Copenhagen, the city in which it was discovered
3-MINUTE REACTION
Hafnium is not a particularly rare element, but it was difficult to extract because it is so similar to the element zirconium that lies directly above it in the periodic table. The two elements typically occur together in minerals such as zircon or ZrSiO4. Hafnium absorbs neutrons well and is used for that purpose in nuclear reactors.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
GEORGES URBAIN
1872–1938
French chemist who falsely claimed in 1911 to have discovered element 72, which he called celtium
GEORGE DE HEVESY
1885–1966
Hungarian radiochemist, co-discoverer of hafnium
DIRK COSTER
1889–1950
Dutch physicist, co-discoverer of hafnium
30-SECOND TEXT
Eric Scerri
Hafnium is extracted from zirconium minerals for use in alloys and the control rods needed within nuclear power stations.
The element rhenium lies two places below manganese in group 7 of the periodic table. Its existence, as well as that of an element above it, were predicted by Russian chemist Dmitri Mendeleev in 1869. Rhenium was finally discovered in 1925 by Walter Noddack, Ida Tacke (later Noddack) and Otto Berg in Germany. After an extraction of heroic proportions, they obtained around 1 g (1/25 oz) of rhenium by processing about 660 kg (1,450 pounds) of the ore molybdenite. Until quite recently, no mineral containing rhenium combined only with a non-metal had been found. In 1992, however, a team of Russian scientists discovered rhenium disulphide at the mouth of a volcano on an island off the east coast of Russia. In contrast to many other metals, rhenium does not undergo transformation from ductile to brittle as its melting point is approached. It retains a very high strength at high temperatures in addition to very good ductility, making it an ideal choice for high-temperature applications. Recently, a simple compound, rhenium dibromide, has attracted attention as one of the hardest known substances; unlike other superhard materials, it does not have to be manufactured under high pressure.
3-SECOND STATE
Element symbol: Re
Atomic number: 75
Named: From Rhenus (Latin for the river ‘Rhine’)
3-MINUTE REACTION
Rhenium shows the largest range of oxidation states of any known element, namely -1, 0, +1, +2 and so on all the way to +7, the last of which is its most common oxidation state. It is also the metal that led to the discovery of the first metal-to-metal quadruple bond as found in 1964 in the rhenium ion [Re2Cl8]2-.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
WALTER & IDA NODDACK
1893–1960 & 1896–1978
German chemists, co-discoverers of rhenium
ALBERT COTTON
1930–2007
American chemist, prepared the first metal compound with a quadruple metal-metal bond using rhenium
30-SECOND TEXT
Eric Scerri
The very hard-wearing, silvery metal rhenium resists corrosion and has been used in electrical contacts and in the nibs of fountain pens. It can be made into wire and foil.
Technically a transition metal (part of a large block in the centre of the periodic table), gold is used above all in jewellery and as currency – reflecting its ease of working, its rarity and its attractive shine. It differs from the usual silvery colour of metals because some of its electrons move so fast (close to the speed of light) that relativistic effects change the shape of their orbits, altering the energy of the photons they absorb and re-emit. Because gold is so dense, practically all the earth’s gold is thought to be deep within the planet. The metal we dig up arrived later, when gold-bearing asteroids and meteorites hit the earth’s surface. It has been estimated that all the gold ever mined would form a block around the size of a small office block – 8,000 m3 (282,500 cu ft). From earliest times, gold has found its way into jewellery, and this still accounts for around 50 per cent of production; another 40 per cent is transformed into gold bars and coinage. The remainder has the most practical usage: because it doesn’t oxidize in air and is a great conductor, gold is often used for circuit boards, plugs and electrical contacts.
3-SECOND STATE
Chemical symbol: Au
Atomic number: 79
Named: From the old German ghol (prefix for yellow)
3-MINUTE REACTION
Gold is not highly reactive, which is why it stays shiny, not oxidizing in air, but it will dissolve in aqua regia, a mix of concentrated nitric and hydrochloric acids. It is classed as a noble metal alongside silver, platinum and others, because filled bands in its electronic structure give it low reactivity. It can react, though, typically producing compounds such as gold chlorides AuCl and Au2Cl6.
RELATED ELEMENTS
3-SECOND BIOGRAPHY
ARCHIMEDES
c. 287–c. 212 BCE
Greek philosopher who tested gold’s density by dunking it into water
PEKKA PYKKÖ
1942–
Finnish quantum chemist who has predicted several new compounds of gold
30-SECOND TEXT
Brian Clegg
Gold has been known for at least 6000 years. Its lure, which finds it coating everything from Olympic medals to Oscars, remains its luxurious, glittery scarcity.
Mercury is the only liquid metal and, with bromine, one of only two elements that is liquid at room temperature. Its liquid nature makes it distractingly beautiful: the Islamic rulers of medieval Spain placed mercury pools in their gardens in which visitors could dabble their fingers. The element is usually obtained from its ore cinnabar or vermilion (mercury sulphide), which is also the pigment used to produce the red colour used in some Hindu rituals. Mercury has been used as a medicine for thousands of years in forms such as the laxative calomel and the disinfectant mercurochrome; more strongly reactive compounds were used to treat syphilis. Mercury is especially favoured in Chinese medicine. The element is nevertheless highly poisonous. Mercury used to treat animal fur in hat-making produced acute psychological as well as physical symptoms of illness, inspiring the phrase ‘as mad as a hatter’ and the character of the Hatter in Lewis Carroll’s 1865 novel Alice’s Adventures in Wonderland. Less toxic substitutes are being found for many of mercury’s uses, in measurement instruments, valves, switches and dental amalgams. However, other applications such as in energy-saving compact fluorescent bulbs are increasing demand for the element.
3-SECOND STATE
Chemical symbol: Hg
Atomic number: 80
Named: From its alchemical and astrological links to the planet Mercury
3-MINUTE REACTION
The chemical behavior of mercury sulphide was of great interest to alchemists, who hoped that combining sulphur with mercury might produce gold. Later, chemists saw that this reversible reaction (heating mercury and sulphur leads to the sulphide; heating again makes it break up into its constituents) provided a clue that elements can be neither created nor destroyed. British natural philosopher Joseph Priestley exploited the similar reactions of mercury oxide in his experiments with oxygen in 1774.
RELATED ELEMENTS
3-SECOND BIOGRAPHIES
EVANGELISTA TORRICELLI
1608–47
Italian inventor of the mercury barometer in 1643
DANIEL FAHRENHEIT
1686–1736
Dutch-German-Polish inventor of the mercury thermometer
ALEXANDER CALDER
1898–1976
American creator of 1937 artwork ‘Mercury Fountain’
30-SECOND TEXT
Hugh Aldersey-Williams
Poisonous but beautiful, mercury caused the madness of hatters in the work of Lewis Carroll. Today, it is used safely in instruments and fluorescent bulbs.
Right now it probably doesn’t exist. Copernicium is one of a group of superheavy elements made artificially in a particle accelerator by colliding ions into a heavy-metal target; and, like the other superheavy elements, it is radioactive and decays very quickly. The longest-lived isotope, copernicium-285, has a half-life of just 29 seconds. These elements are made atom by atom, and, in total, just 75 atoms of copernicium have been detected so far. The element was first produced in 1996 by firing zinc ions into lead at the GSI Center for Heavy Ion Research in Darmstadt, Germany – the birthplace of several other artificial elements. The German claims were not officially recognized until 2009, when the team proposed to name the new element after Polish astronomer Nicolaus Copernicus. That name wasn’t accepted until 19 February 2010, the 537th anniversary of Copernicus’s birth. By that time copernicium had been synthesized by other groups in Russia and Japan. Investigating copernicium’s chemical properties is greatly challenging, given so little material (a few atoms) and so short a time (just a few seconds). Its place in the periodic table suggests it should be similar to mercury, forming chemical bonds to gold – and that’s what experiments so far seem to confirm.
3-SECOND STATE
Chemical symbol: Cn
Atomic number: 112
Named: After the Polish astronomer Nicolaus Copernicus (1473–1543)
3-MINUTE REACTION
Copernicium is the heaviest of the elements in group 12 of the periodic table – which also includes zinc, cadmium and mercury. In a copernicium atom, the huge nucleus – with a very large positive charge – distorts energy levels through the electron shells because of the effects of special relativity with some of the electrons moving so fast that they gain mass. This has knock-on effects that may make copernicium exhibit the behaviour of a noble gas.
RELATED ELEMENTS
3-SECOND BIOGRAPHY
SIGURD HOFMANN
1944–
German chemist, leader of the team that discovered copernicium in 1996
30-SECOND TEXT
Philip Ball
Superheavy element copernicium is the product of experiments in an ion accelerator. The first time it was produced, just one single atom of copernicium-277 was created.
