Category:Discoverers of chemical elements
Pages in category "Discoverers of chemical elements"
The following 101 pages are in this category, out of 101 total. This list may not reflect recent changes (learn more).
The following 101 pages are in this category, out of 101 total. This list may not reflect recent changes (learn more).
1. Chemist – A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties, chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists carefully measure substance proportions, reaction rates, and other chemical properties, the word chemist is also used to address Pharmacists in Commonwealth English. Chemists may specialize in any number of subdisciplines of chemistry, materials scientists and metallurgists share much of the same education and skills with chemists. The roots of chemistry can be traced to the phenomenon of burning, fire was a mystical force that transformed one substance into another and thus was of primary interest to mankind. It was fire that led to the discovery of iron and glasses, after gold was discovered and became a precious metal, many people were interested to find a method that could convert other substances into gold. This led to the protoscience called alchemy, the word chemist is derived from the New Latin noun chimista, an abbreviation of alchimista. Alchemists discovered many chemical processes that led to the development of modern chemistry, Chemistry as we know it today, was invented by Antoine Lavoisier with his law of conservation of mass in 1783. The discoveries of the elements has a long history culminating in the creation of the periodic table by Dmitri Mendeleev. The Nobel Prize in Chemistry created in 1901 gives an excellent overview of chemical discovery since the start of the 20th century. Jobs for chemists usually require at least a degree, but many positions, especially those in research. At the Masters level and higher, students tend to specialize in a particular field, postdoctoral experience may be required for certain positions. Workers whose work involves chemistry, but not at a complexity requiring an education with a degree, are commonly referred to as chemical technicians. Such technicians commonly do such work as simpler, routine analyses for quality control or in clinical laboratories, there are also degrees specific to become a Chemical Technologist, which are somewhat distinct from those required when a student is interested in becoming a professional Chemist. A Chemical technologist is more involved in the management and operation of the equipment and they are part of the team of a chemical laboratory in which the quality of the raw material, intermediate products and finished products is analyzed. They also perform functions in the areas of quality control. The higher the level achieved in the field of Chemistry, the higher the responsibility given to that chemist. Chemistry, as a field, have so many applications that different tasks/objectives can be given to workers/scientists with these different levels of education and/or experience
2. Chemical element – A chemical element or element is a species of atoms having the same number of protons in their atomic nuclei. There are 118 elements that have identified, of which the first 94 occur naturally on Earth with the remaining 24 being synthetic elements. There are 80 elements that have at least one stable isotope and 38 that have exclusively radioactive isotopes, iron is the most abundant element making up Earth, while oxygen is the most common element in the Earths crust. Chemical elements constitute all of the matter of the universe. The two lightest elements, hydrogen and helium, were formed in the Big Bang and are the most common elements in the universe. The next three elements were formed mostly by cosmic ray spallation, and are rarer than those that follow. Formation of elements with from 6 to 26 protons occurred and continues to occur in main sequence stars via stellar nucleosynthesis, the high abundance of oxygen, silicon, and iron on Earth reflects their common production in such stars. The term element is used for atoms with a number of protons as well as for a pure chemical substance consisting of a single element. A single element can form multiple substances differing in their structure, when different elements are chemically combined, with the atoms held together by chemical bonds, they form chemical compounds. Only a minority of elements are found uncombined as relatively pure minerals, among the more common of such native elements are copper, silver, gold, carbon, and sulfur. All but a few of the most inert elements, such as gases and noble metals, are usually found on Earth in chemically combined form. While about 32 of the elements occur on Earth in native uncombined forms. For example, atmospheric air is primarily a mixture of nitrogen, oxygen, and argon, the history of the discovery and use of the elements began with primitive human societies that found native elements like carbon, sulfur, copper and gold. Later civilizations extracted elemental copper, tin, lead and iron from their ores by smelting, using charcoal, alchemists and chemists subsequently identified many more, almost all of the naturally occurring elements were known by 1900. Save for unstable radioactive elements with short half-lives, all of the elements are available industrially, almost all other elements found in nature were made by various natural methods of nucleosynthesis. On Earth, small amounts of new atoms are produced in nucleogenic reactions, or in cosmogenic processes. Of the 94 naturally occurring elements, those with atomic numbers 1 through 82 each have at least one stable isotope, Isotopes considered stable are those for which no radioactive decay has yet been observed. Elements with atomic numbers 83 through 94 are unstable to the point that radioactive decay of all isotopes can be detected, the very heaviest elements undergo radioactive decay with half-lives so short that they are not found in nature and must be synthesized
3. Periodic table – The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configurations, and recurring chemical properties. This ordering shows periodic trends, such as elements with similar behaviour in the same column and it also shows four rectangular blocks with some approximately similar chemical properties. In general, within one row the elements are metals on the left, the rows of the table are called periods, the columns are called groups. Six groups have names as well as numbers, for example, group 17 elements are the halogens, and group 18, the noble gases. The periodic table can be used to derive relationships between the properties of the elements, and predict the properties of new elements yet to be discovered or synthesized, the periodic table provides a useful framework for analyzing chemical behaviour, and is widely used in chemistry and other sciences. The Russian chemist Dmitri Mendeleev published the first widely recognized periodic table in 1869 and he developed his table to illustrate periodic trends in the properties of the then-known elements. Mendeleev also predicted some properties of elements that would be expected to fill gaps in this table. Most of his predictions were proved correct when the elements in question were subsequently discovered, Mendeleevs periodic table has since been expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behaviour. The first 94 elements exist naturally, although some are only in trace amounts and were synthesized in laboratories before being found in nature. Elements with atomic numbers from 95 to 118 have only been synthesized in laboratories or nuclear reactors, synthesis of elements having higher atomic numbers is being pursued. Numerous synthetic radionuclides of naturally occurring elements have also produced in laboratories. Each chemical element has an atomic number representing the number of protons in its nucleus. Most elements have differing numbers of neutrons among different atoms, with variants being referred to as isotopes. Isotopes are never separated in the table, they are always grouped together under a single element. Elements with no stable isotopes have the masses of their most stable isotopes. In the standard periodic table, the elements are listed in order of increasing atomic number, a new row is started when a new electron shell has its first electron. Columns are determined by the configuration of the atom, elements with the same number of electrons in a particular subshell fall into the same columns. Thus, it is easy to predict the chemical properties of an element if one knows the properties of the elements around it
4. Philip Abelson – Philip Hauge Abelson was an American physicist, a scientific editor, and a science writer. Abelson was born on April 27,1913, in Tacoma and he attended Washington State University, where he received degrees in chemistry and physics, and the University of California, Berkeley, where he earned his PhD in nuclear physics. As a young physicist, he worked for Ernest Lawrence at the UC Berkeley and he was among the first American scientists to verify nuclear fission in an article submitted to the Physical Review in February 1939. From 1939 until 1941, he worked as an assistant physicist at the Carnegie Institution in Washington DC and it was while he was here that he worked on a substance that emitted beta rays and was produced by irradiation of uranium with neutrons. After he collaborated with the Nobel Prize laureate Luis Alvarez they isolated the material, McMillan was awarded the Nobel Prize for this discovery among other elements. Abelson was a key contributor to the Manhattan Project during World War II, after the war, he turned his attention under the guidance of Ross Gunn to applying nuclear power to naval propulsion. While not written at a level, he wrote the first physics report detailing how a nuclear reactor could be installed in a submarine. His report anticipated the nuclear role as a missile platform. This concept was supported by Admiral Hyman G. Rickover. Under Rickover, the concept became reality in the form of USS Nautilus, from 1962 to 1984 he was editor of Science, one of the most prestigious academic journals, and served as its acting executive officer in 1974,1975 and 1984. From 1972 until 1974 he served as the president of the American Geophysical Union, Abelson was outspoken and well known for his opinions on science. In a 1964 editorial published in Science magazine, Abelson identified overspecialization in science as a form of bigotry and he estimated that based on his experiments alanine would be stable for billions of years. Perhaps his most famous work from time period is an editorial entitled Enough of Pessimism. This became the title of a 100 essay collection, during the 1970s he became interested in the problem of world energy supplies. Books on the topic include Energy for Tomorrow, from a series of lectures at the University of Washington and he pointed out the possibilities of mining the Athabascan tar sands, as well as oil shale in the Colorado Rockies. In addition he urged conservation and a change of attitude towards public transit, after 1984, he remained associated with the magazine. This would exceed by far the temperature fluctuations of the past several years and would very likely. Abelson died on August 1,2004, from complications following a brief illness
5. Albertus Magnus – Albertus Magnus, O. P. also known as Saint Albert the Great and Albert of Cologne, was a German Dominican friar and Catholic bishop. Later canonised as a Catholic saint, he was known during his lifetime as doctor universalis and doctor expertus and, late in his life, the term magnus was appended to his name. Scholars such as James A. Weisheipl and Joachim R. Söder have referred to him as the greatest German philosopher, the Catholic Church distinguishes him as one of the 36 Doctors of the Church. It seems likely that Albert was born sometime before 1200, given well-attested evidence that he was aged over 80 on his death in 1280. More than one source says that Albert was 87 on his death, Albert was probably born in Lauingen, since he called himself Albert of Lauingen, but this might simply be a family name. Most probably his family was of class, his familiar connection with Bollstädt noble family was a 15th-century misinterpretation that is now completely disproved. Albert was probably educated principally at the University of Padua, where he received instruction in Aristotles writings, a late account by Rudolph de Novamagia refers to Albertus encounter with the Blessed Virgin Mary, who convinced him to enter Holy Orders. In 1223 he became a member of the Dominican Order, and studied theology at Bologna and elsewhere. Selected to fill the position of lecturer at Cologne, Germany, where the Dominicans had a house, he taught for years there, as well as in Regensburg, Freiburg, Strasbourg. During his first tenure as lecturer at Cologne, Albert wrote his Summa de bono after discussion with Philip the Chancellor concerning the properties of being. In 1245, Albert became master of theology under Gueric of Saint-Quentin, following this turn of events, Albert was able to teach theology at the University of Paris as a full-time professor, holding the seat of the Chair of Theology at the College of St. James. During this time Thomas Aquinas began to study under Albertus, Albert was the first to comment on virtually all of the writings of Aristotle, thus making them accessible to wider academic debate. The study of Aristotle brought him to study and comment on the teachings of Muslim academics, notably Avicenna and Averroes, in 1254 Albert was made provincial of the Dominican Order, and fulfilled the duties of the office with great care and efficiency. During the exercise of his duties he enhanced his reputation for humility by refusing to ride a horse, in accord with the dictates of the Order and this earned him the affectionate sobriquet boots the bishop from his parishioners. In 1263 Pope Urban IV relieved him of the duties of bishop, after this, he was especially known for acting as a mediator between conflicting parties. Among the last of his labors was the defense of the orthodoxy of his pupil, Thomas Aquinas. After suffering a collapse of health in 1278, he died on November 15,1280, in the Dominican convent in Cologne, since November 15,1954, his relics are in a Roman sarcophagus in the crypt of the Dominican St. Andreas Church in Cologne. Although his body was discovered to be incorrupt at the first exhumation three years after his death, at the exhumation in 1483 only a skeleton remained
6. Johan August Arfwedson – Johan August Arfwedson was a Swedish chemist who discovered the chemical element lithium in 1817 by isolating it as a salt. Arfwedson belonged to a bourgeois family, the son of the wholesale merchant and factory owner Jacob Arfwedson and his spouse. The younger Arfwedson matriculated as a student at the University of Uppsala in 1803, completed a degree in Law in 1809, in the latter year, he received an unpaid position in the Royal Board of Mines, where he advanced to the position of notary in 1814. In Stockholm, Arfwedson knew the chemist Jöns Jakob Berzelius and received access to his private laboratory, the actual isolation of lithium metal would be done by others. In 1818 and 1819, Arfwedson made a European journey, partly in the society of Berzelius, after coming home, Arfwedson built his own laboratory on his estate. He spent the part of his remaining life administering and multiplying his inherited wealth. He was elected a member of the Royal Swedish Academy of Sciences in 1821, the rare mineral arfvedsonite was named after him. Humphry Davy William Thomas Brande Weeks, Mary Elvira, Larson, Mary E. J. A. Arfwedson and his Services to Chemistry
7. Carl Auer von Welsbach – Carl Auer was born in Vienna on 1 September 1858 to Therese and Alois Auer. Alois, ennobled in 1860, was director of the Imperial printing office in the days of the Austrian Empire, Carl went to high schools in Mariahilf and Josefstadt. After leaving school in 1877, he joined the Austro-Hungarian Army and was commissioned as a Second Lieutenant, in 1878 Auer entered the University of Vienna, studying mathematics, general chemistry, engineering physics, and thermodynamics. He then moved to the University of Heidelberg in 1880, where he continued his studies in chemistry under the direction of Robert Bunsen, in 1885, Von Welsbach used a method that he developed himself to separate the alloy didymium into its two parts for the first time. He saw several different colored versions which he named praseodymium and neodidymium, to produce a mantle, guncotton is impregnated with a mixture of Actinophor and then heated, the cotton eventually burns away leaving a solid ash which glows brightly when heated. These original mantles gave off a light and were not very successful. In 1890 he introduced a new form of the based on a mixture of 99% thorium dioxide. These proved both more robust as well as having a whiter light. Another company founded to produce the design was formed in 1891, working with fellow student from the university Ignaz Kreidl. He then started work on development of metal-filament mantles, first with platinum wiring, osmium is very difficult to work with, but he developed a new method which mixed osmium oxide powder with rubber or sugar into a paste, which is then squeezed through a nozzle and fired. The paste burns away, leaving a fine wire of osmium and he worked on this until finally developing a workable technique in 1898, and started a new factory to produce his Auer-Oslight, which he introduced commercially in 1902. In 1903 Auer von Welsbach won another patent for a fire striker composition named ferrocerium, welsbachs flints consisted of pyrophoric alloys, 70% cerium and 30% iron, which when scratched or struck would give off sparks. This system remains in use in cigarette lighters today. In 1907 he formed Treibacher Chemische Werke GesmbH to build and market the devices, in 1920 he received the Siemens-Ring as his name had become a synonym for the rise of artificial lightning. Over the rest of his life he turned again to pure chemistry and published a number of papers on chemical separation and he presented a major paper on his work on the separation of radioactive elements in 1922. In 2008 Auer von Welsbach was selected as a motif for a high value collectors coin. The reverse has a portrait of Auer on the left hand side. Wilhelm Exner Medal, inaugural awardee,1921 Auergesellschaft Auerlite Weeks, the discovery of the elements, XVI