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Sir William Crookes was a British chemist and physicist who attended the Royal College of Chemistry, now part of Imperial College London, and worked on spectroscopy. He was a pioneer of vacuum tubes, inventing the Crookes tube which was made in 1875. This was a foundational discovery that eventually changed the whole of chemistry and physics.
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Paul-Émile Lecoq de Boisbaudran, also called François Lecoq de Boisbaudran, was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium. He developed methods for separation and purification of the rare earth elements and was one of the pioneers of the science of spectroscopy.
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Jean Charles Galissard de Marignac was a Swiss chemist whose work with atomic weights suggested the possibility of isotopes and the packing fraction of nuclei. His study of the rare earth elements led to his discovery of ytterbium in 1878 and co-discovery of gadolinium in 1880.
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Johan Gadolin was a Finnish chemist, physicist and mineralogist. Gadolin discovered a "new earth" containing the first rare-earth compound yttrium, which was later determined to be a chemical element. He is also considered the founder of Finnish chemistry research, as the second holder of the Chair of Chemistry at the Royal Academy of Turku. Gadolin was ennobled for his achievements and awarded the Order of Saint Vladimir and the Order of Saint Anna.
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Georges Urbain was a French chemist, a professor of the Sorbonne, a member of the Institut de France, and director of the Institute of Chemistry in Paris. Much of his work focused on the rare earths, isolating and separating elements such as europium and gadolinium, and studying their spectra, their magnetic properties and their atomic masses. He discovered the element lutetium. He also studied the efflorescence of saline hydrates.
Carl Axel Arrhenius was a Swedish military officer, amateur geologist, and chemist. He is best known for his discovery of the mineral ytterbite in 1787.
Claude Auguste Lamy was a French physicist and chemist chemist who discovered the element thallium independently from William Crookes in 1862; as a result, they are considered co-discoverers, although they did not collaborate.
Larned (Larry) Brown Asprey was an American chemist noted for his work on actinide, lanthanide, rare-earth, and fluorine chemistry, and for his contributions to nuclear chemistry on the Manhattan Project and later at the Los Alamos National Laboratory.
Terbium compounds are compounds formed by the lanthanide metal terbium (Tb). Terbium generally exhibits the +3 oxidation state in these compounds, such as in TbCl3, Tb(NO3)3 and Tb(CH3COO)3. Compounds with terbium in the +4 oxidation state are also known, such as TbO2 and BaTbF6. Terbium can also form compounds in the 0, +1 and +2 oxidation states.
References
- ↑ Elder, Eleanor S (1980). "Sir William Crookes, Victorium, and the Library of Congress". Journal of Chemical Education. 57 (6): 421. Bibcode:1980JChEd..57..421E. doi:10.1021/ed057p421.
- ↑ Fontani, Marco; Costa, Mariagrazia; Orna, Mary Virginia (2014). The Lost Elements: The Periodic Table's Shadow Side. Oxford University Press. pp. 202–203. ISBN 9780199383368.
- ↑ Brock, William Hodson (2008). William Crookes (1832-1919) and the Commercialization of Science. Ashgate Publishing. pp. 321–325. ISBN 9780754663225.
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