Cerite earth
Cerite earth is a collective term for the oxides of a series of chemical elements from the group of lanthanoids , named after the first element in this series, cerium . It includes oxides of the elements with atomic numbers 58 to 64: cerium, praseodymium , neodymium , promethium , samarium , europium and gadolinium . The following lanthanide oxides are referred to analogously as ytter earths . All lanthanoids in turn belong to the group of rare earth metals .
history
At the beginning of the 19th century, the Swedish chemist Jöns Jakob Berzelius discovered a previously unknown soil in a cerite sample, which he called " cerite earth" , analogous to the sample examined. From the end of the 1830s, his student Carl Gustav Mosander succeeded in further analyzing and breaking down these and other compounds from the series of cerite and ytter earths into the chemical elements of the lanthanides.
Occurrence
Among all lanthanides, the cerite earths are significantly more common than the ytter earths. Cerium is the most common rare earth , followed by neodymium. Europium, the rarest earth, is about as abundant in the upper crust as silver and is still more abundant than gold or platinum.
Individual evidence
- ^ A b c A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 91st – 100th, improved and greatly expanded edition. Walter de Gruyter, Berlin 1985, ISBN 3-11-007511-3 , pp. 1266-1268.