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Lanthanum is the first element and prototype of the lanthanide series. In the periodic table, it appears to the right of the alkaline earth metal barium and to the left of the lanthanide cerium. Lanthanum is generally considered the first of the f-block elements by authors writing on the subject.
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals.
The term derives from lanthanum, first discovered in 1838, at that time a so-called new rare-earth element "lying hidden" or "escaping notice" in a cerium mineral, [12] and it is an irony that lanthanum was later identified as the first in an entire series of chemically similar elements and gave its name to the whole series.
Prepared and isolated from urine, it was the first element whose discovery date and discoverer are recorded. [53] Its name first appears in print in the work of Georg Kaspar Kirchmayer in 1676. Recognised as an element by Lavoisier. [3] 1 Hydrogen: 1671 R. Boyle: 1671 R. Boyle Robert Boyle produced it by reacting iron filings with dilute acid.
[10]: 68 Potassium was the first metal that was isolated by electrolysis. [11] Later that same year, Davy reported extraction of sodium from the similar substance caustic soda (NaOH, lye) by a similar technique, demonstrating the elements, and thus the salts, to be different. [8] [9] [12] [13]
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
According to the Institute of Geology, Ukraine possesses rare earth elements such as lanthanum and cerium, used in TVs and lighting, neodymium, used in wind turbines and EV batteries, as well as ...
The first transition series is present in the 4th period, and starts after Ca (Z = 20) of group 2 with the configuration [Ar]4s 2, or scandium (Sc), the first element of group 3 with atomic number Z = 21 and configuration [Ar]4s 2 3d 1, depending on the definition used. As we move from left to right, electrons are added to the same d subshell ...