Per Teodor Cleve
|Per Teodor Cleve|
Per Teodor Cleve
|Born||10 February 1840
|Died||18 June 1905
|Alma mater||Stockholm Gymnasium (1858)
Uppsala University (1863)
|Known for||Discovery of holmium and thulium|
Per Teodor Cleve (February 10, 1840 to June 18, 1905) was a Swedish chemist, biologist, mineralogist, oceanographer, and professor. He discovered the chemical elements holmium and thulium and helped to isolate helium from the uranium ore cleveite. Cleve was born in Stockholm to F.T. Cleve. He became an assistant professor at the University of Uppsala in 1860. Cleve died several months after contracting pleurisy in 1904.
Cleve was born in February 10, 1840 in Stockholm, Sweden, the thirteenth child of his father. His father was a merchant named F.T. Cleve. Cleve's ancestor's on his father's side originally came from western Germany and settled in Sweden in the late 18th century.
Cleve exhibited interest in natural science and natural history from an early age. He attended high school at the Stockholm Gymnasium in 1858, studying chemistry and biology. He gained a Bachelor of Science degree from the University of Uppsala in 1863 and a PhD from the same university in 1868.
Cleve gained a post as an assistant professor of mineralogy in 1860, at the age of 20. He gained the post of assistant professor of chemistry at the University of Uppsala in 1868. He also taught at the Technological Institute in Stockholm between 1870 and 1874 at the University of Uppsala and he eventually became a professor of general and agricultural chemistry. He was the chair of chemistry at the University of Uppsala starting in 1874. He was also the president of the Nobel Trusts chemistry committee.
Cleve's first work was Några ammoniakaliska chromföreningar, which translates to Some Compounds. He wrote it in 1861 on a complex compound of chromium. He also wrote several more papers on complex compounds, including the compounds of platinum. Additionally, Cleve synthesized several hundred complex platinum compounds.
Cleve visited a number of laboratories in England, France, Italy, and Switzerland in the 1860s. While in Paris, he visited the laboratory of Charles Adolphe Wurtz and also made a number of friends there.
Cleve worked on the synthesis of complex chemical compounds until 1872. He theorized in 1874 that the element didymium consisted of two elements. This theory was proven right with the discovery of praseodymium and neodymium in 1885 by C.A. Welsbach. In 1879, Cleve proved that the newly discovered element scandium was an element predicted by Dimitri Mendeleev to be "eka-boron". He also isolated a quantity of scandium in this same year and determined its atomic weight. He discovered the element holmium in 1879 by examining a sample of erbium oxide. While removing impurities from a sample of erbium oxide, Cleve discovered a brown substance and a green substance, and the brown substance was holmium oxide (the green substance was thulium oxide). However, this sample may have been impure. He also separated thulium from an erbium oxide sample in 1879. Additionally, Cleve and Abraham Langlet discovered helium in the mineral clevite in 1895. Cleve and Langlet also correctly determined the atomic weight of helium.
Cleve discovered six forms of dichloronaphthalene and also discovered aminonaphthalenesulfonic acids, which are sometimes named after him. He also prepared a number of nitrosulfonic acids as well. In 1883, Cleve was the first person to describe the plankton species Nitzschia seriata. In 1890, Cleve began to mainly focus on the field of biology, mainly studying freshwater algae, diatoms, and plankton. Cleve participated in a Swedish expedition to Spitsbergen in 1898. While on this mission, he discovered a number of species of spumellarians, nassellarians, and phaeodarians.
Cleve, in collaboration with Höglund prepared numerous previously-undiscovered salts of yttrium and erbium. The two also did work on the chemistry of the chemical elements thorium and lanthanum. By 1874, Cleve discovered that thorium was a quadrivalent element and also determined lanthanum to be trivalent. These findings were initially doubted by the scientific community.
Cleve's PhD dissertation was "Mineral-analytiska under-sökningar". He also wrote a paper on samarium in 1879 and The Seasonal Distribution of Atlantic Plankton Organisms in 1900. He also wrote Kemiskt Handlexicon, which translates to Chemical Handbook, in 1883. Notable students of Cleve include Ellen Fries (the first Swedish woman to earn a PhD) and Svante Arrhenius (a winner of the Nobel Prize).
Personal life, family, and death
Cleve married Alma Öhbom, a teacher, in 1874. He had three daughters, the first of whom was Astrid M. Cleve, who became a botanist. She was born on January 22, 1875. His son-in-law and grandson, Hans von Euler-Chelpin and Ulf von Euler, both won Nobel Prizes. Cleve was friends with Thomas Edward Thorpe.
Cleve supported women's equality. In 1883, at the conferring of a PhD on Ellen Fries, Cleve considered it to be "a sign of civilization and cultural progress that women were allowed to attain higher positions in society".
Awards and legacy
- Per Teodor Cleve, Encyclopedia Britannica, retrieved March 13, 2014
- Charles Scribner's Sons (2008), Cleve, Per Teodor, retrieved March 13, 2014
- Jerry Coffey (February 2, 2010), Who Discovered Helium?, retrieved March 14, 2014
- Per Theodor Cleve, retrieved March 13, 2014
- Chemical Society (Great Britain), Sir Humphry Davy, Bureau of Chemical Abstracts (Great Britain) (June 21, 1906), The collected works of Sir Humphry Davy ...: Discourses delivered before the Royal society. Elements of agricultural chemistry, pt. I, retrieved March 14, 2014
- Per Theodor Cleve, retrieved March 14, 2014
- Ole Bostrup (2004), Cleve, Per Theodor, retrieved March 14, 2014
- Ira Remsen, Charles August Rouillu, ed. (1905), American Chemical Journal, Volume 34, retrieved March 14, 2014
- Doug Stewart, Holmium Element Facts / Chemistry, retrieved March 14, 2014
- Introduction to Holmium, retrieved March 14, 2014
- John Emsley (2011), Nature's Building Blocks An A-Z Guide to the Elements New Edition, p. 224,225, retrieved March 13, 2014
- John Emsley (2011), Nature's Building Blocks An A-Z Guide to the Elements New Edition, p. 549, retrieved March 13, 2014
- Giora Shaviv (October 3, 2009), Life of Stars: The Controversial Inception and Emergence of the Theory of Stellar Structure, retrieved March 13, 2014
- Kjell R. Bjørklund, Takuya Itaki, Jane K. Dolven (November 26, 2012), Per Theodor Cleve: a short résumé and his radiolarian results from the Swedish Expedition to Spitsbergen in 1898, retrieved March 14, 2014
- Data Research Analyst, Worldofchemicals.com (February 9, 2013), Per Teodor Cleve – discoverer of Holmium & Thulium elements, retrieved March 14, 2014
- Ladies in the Laboratory 2, January 1, 2004, retrieved March 13, 2014
- Annette Lykknes, Donald L. Opitz, Brigitte Van Tiggelen (June 5, 2012), For Better or For Worse? Collaborative Couples in the Sciences