Mosander

In 1843 Mosander showed that yttira could be resolved into the oxides (or earths) of three elements. The name yttria was reserved for the most basic one the others were named erbia and terbia. 

Greek lanthanein, to lie hidden) Mosander in 1839 extracted a new earth lanthana, from impure cerium nitrate and recognized the new element. 

Gr. prasios, green, and didymos, twin) In 1841 Mosander extracted the rare earth didymia from lanthana in 1879, Lecoq de Boisbaudran isolated a new earth, samaria, from didymia obtained from the mineral samarskite. Six years later, in 1885, von Welsbach separated didymia into two others, praseodymia and neodymia, which gave salts of different colors. As with other rare earths, compounds of these elements in solution have distinctive sharp spectral absorption bands or lines, some of which are only a few Angstroms wide. 

Gr. neos, new, and didymos, twin) In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he believed contained a new element. He named the element didymium, as it was an inseparable twin brother of lanthanum. In 1885 von Welsbach separated didymium into two new elemental components, neodymia and praseodymia, by repeated fractionation of ammonium didymium nitrate. While the free metal is in misch metal, long known and used as a pyrophoric alloy for light flints, the element was not isolated in relatively pure form until 1925. Neodymium is present in misch metal to the extent of about 18%. It is present in the minerals monazite and bastnasite, which are principal sources of rare-earth metals. 

From gadolinite, a mineral named for Gadolin, a Finnish chemist. The rare earth metal is obtained from the mineral gadolinite. Gadolinia, the oxide of gadolinium, was separated by Marignac in 1880 and Lecoq de Boisbaudran independently isolated it from Mosander s yttria in 1886. 

Ytterby, a village in Sweden) Discovered by Mosander in 1843. Terbium is a member of the lanthanide or "rare earth" group of elements. It is found in cerite, gadolinite, and other minerals along with other rare earths. It is recovered commercially from monazite in which it is present to the extent of 0.03%, from xenotime, and from euxenite, a complex oxide containing 1% or more of terbia. 

In 1794 the Finnish chemist J. Gadolin, while examining a mineral that had recently been discovered in a quarry at Ytterby, near Stockholm, isolated what he thought was a new oxide (or earth ) which A. G. Ekeberg in 1797 named yttria. In fact it was a mixture of a number of metal oxides from which yttrium oxide was separated by C. G. Mosander in 1843. This is actually part of the fascinating story of the rare earths to which we shall return in Chapter 30. The first sample of yttrium metal, albeit very impure, was obtained by F. Wohler in 1828 by the reduction of the trichloride by potassium. 

Four years before isolating yttria, Mosander extracted lanthanum oxide as an impurity from cerium nitrate (hence the name from Greek XavOaveiv, to hide), but it was not until 1923 that metallic lanthanum in a relatively pure form was obtained, by electrolysis of fused halides. 

In 1751 the Swedish mineralogist, A. F. Cronstedt, discovered a heavy mineral from which in 1803 M. H. Klaproth in Germany and, independently, i. i. Berzelius and W. Hisinger in Sweden, isolated what was thought to be a new oxide (or earth ) which was named ceria after the recently discovered asteroid, Ceres. Between 1839 and 1843 this earth, and the previously isolated yttria (p. 944), were shown by the Swedish surgeon C. G. Mosander to be mixtures from which, by 1907, the oxides of Sc, Y, La and the thirteen lanthanides other than Pm were to be isolated. The small village of Ytterby near Stockholm is celebrated in the names of no less than four of these elements (Table 30.1). 

Lanthanum, La C. G. Mosander 1839 Greek XavQdv LV, lanthanein, to escape notice... 

Carl Gustav Mosander isolated yttrium from the ore. 

Carl Gustav Mosander (1797-1858) The yttrium ore analyzed by Johan Gadolin (1760-1852) in 1794 and the cerium ore discovered by Jons Jakob Berzelius (1779-1848) in 1803 were thought to be the same... 

Lanthanum (La, [Xe]5 / 6.s 2), name and symbol after the Greek name XavOdvciv (lanthanein, to lie hidden). Discovered (1839) by Carl Gustaf Mosander. Silvery white metal. 

This leads to the question of who should be considered the ultimate discoverer of a chemical element Should it be the first person to describe the initial properties, the one who found the oxide or the metal, the one who separated the element or the first one to publish their results On the matter of publication, the Swedish chemist Jons Jacob Berzelius published an annual review (equivalent to our present abstract service) during the early nineteenth century. Berzelius usually cited articles published in other journals, but he also reported on the work in his laboratory which had not yet been published. This enabled his assistant Carl-Gustav Mosander to receive early credit for work that Mosander chose not to formally publish until many years later after he had worked out all of the details. In the element review, we shall see that the answer to the above questions would be any of the above criteria could qualify for discovery of particular elements. 

Erbium - the atomic number is 68 and the chemical symbol is Er. The name derives from the Swedish town of Ytterby (about 3 miles from Stockholm), where the ore gadolinite (in which it was found) was first mined. It was discovered by the Swedish surgeon and chemist Carl-Gustav Mosander in 1843 in an yttrium sample. He separated the yttriiom into yttrium, a rose colored salt... 

Terbium - the atomic number is 65 and the chemical symbol is Tb. The name derives from the village of Ytterby in Sweden, where the mineral ytterbite (the source of terbium) was first found. It was discovered by the Swedish surgeon and chemist Carl-Gustav Mosander in 1843 in an yttrium salt, which he resolved into three elements. He called one yttrium, a rose colored salt he called terbium and a deep yellow peroxide he called erbium. The chemist Berlin detected only two earths in yttrium, i.e., yttrium and the rose colored oxide he called erbium. In 1862, the Swiss chemist Marc Delafontaine reexamined yttrium and found the yellow peroxide. Since the name erbium had now been assigned to the rose colored oxide, he initially called the element mosandrum (after Mosander) but he later reintroduced the name terbium for the yellow peroxide. Thus the original names given to erbium and terbium samples are now switched. Since Bunsen spectroscopically examined Mosander s erbium (now terbium) sample and declared that it was a mixture, the question of who actually discovered terbium, Mosander or Delafontaine remains unresolved to this day. 

Cerium was the first rare-earth element discovered, and its discovery came in 1803 by Jons Jakob Berzelius in Vienna. Johann Gadohn (1760—1852) also studied some minerals that were different from others known at that time. Because they were different from the common earth elements but were all very similar to each other, he named them rare-earth elements. However, he was unable to separate or identify them. In the 1800s only two rare-earths were known. At that time, they were known as yttria and ceria. Carl Gustav Mosander (1797—1858) and several other scientists attempted to separate the impurities in these two elements. In 1839 Mosander treated cerium nitrate with dilute nitric acid, which yielded a new rare-earth oxide he called lanthanum. Mosander is credited with its discovery. This caused a change in the periodic table because the separation produced two new elements. Mosander s method for separating rare-earths from a common mineral or from each other led other chemists to use... 

A stone quarry near the town of Ytterby in Sweden produces a large number of rare-earth elements. Carl Gustaf Mosander (1797-1858) discovered several rare-earths, including the rare-earth mineral gadolinite in this quarry in 1843. He was able to separate gadolinite into three separate, but closely related, rare-earth minerals that he named yttria (which was colorless), erbia (yellow color), and terbia (rose-colored). From these minerals, Mosander identified two new rare-earth elements, terbium and erbium. The terbia that was found was really a compound of terbium terbium oxide (Tb O )... 

In the 1800s chemists searched for new elements by fractionating the oxides of rare-earths. Carl Gustaf Mosander s experiments indicated that pure ceria ores were actually contaminated with oxides of lanthanum, a new element. Mosander also fractionated the oxides of yttria into two new elements, erbium and terbium. In 1878 J. Louis Soret (1827—1890) and Marc Delafontaine (1837-1911), through spectroscopic analysis, found evidence of the element holmium, but it was contaminated by the rare-earth dysprosia. Since they could not isolate it and were unable to separate holmium as a pure rare-earth, they did not receive credit for its discovery. 

Carl Gustaf Mosander, a Swedish chemist, successfully separated two rare-earths from a sample of lanthanum found in the mineral gadolinite. He then tried the same procedure with the rare-earth yttria. He was successful in separating this rare-earth into three separate rare-earths with similar names yttia, erbia, and terbia. For the next 50 years scientists confused these three elements because of their similar names and very similar chemical and physical properties. Erbia and terbia were switched around, and for some time the two rare-earths were mixed up. The confusion was settled ostensibly in 1877 when the chemistry profession had the final say in the matter. However, they also got it wrong. What we know today as erbium was originally terbium, and terbium was erbium. 

Ytterbium is a silvery, soft, malleable, and ductile metal with a lustrous metallic shine. It is slightly reactive in air or water at room temperatures. Ytterbium is located next to last of the rare-earths in the lanthanide series. It slowly oxidizes as it reacts with oxygen in the atmosphere, forming a somewhat duller coating. Ytterbium was the first rare-earth to be discovered by Carl Gustof Mosander in 1843. More of it exists in the Earths crust than once was believed. 

Erbium Er 1842-43 (Stockholm, Sweden) Carl Mosander (Swedish) 297... 

Swedish chemist Carl Gustaf Mosander Silvery, reactive, malleable first of the rare earth elements, whose added electrons are hidden in their atoms interiors as a compound used in high-intensity lighting. 

Swedish chemist Carl Gustaf Mosander Found in the minerals xenotime and euxerite of which it is an impurity soft and malleable metal has few uses other than in inexpensive glass and jewelry. 

Erbium oxide was separated and obtained from the rare earth oxide, yttrea in 1842 by Mosander. Urbain and James independently separated this oxide from other rare earth oxide mixtures in 1905. The pure metal was produced by Klemm and Bommer in 1934 in powdered form. 

The element was discovered hy von Welshach in 1885 after he succeeded in fractionating ammonium didymium nitrate, thus splitting didymia into two new rare earths. Earlier, in 1841, Mosander extracted a rose-colored oxide from cerite, which he named didymium and which actually was a mixture of two rare earth elements. These two new elements were named hy von Welshach as praseodymia (green twin) and neodymia (new twin). 

Mosander extracted from the mineral lanthana a rare earth fraction, named didymia in 1841. In 1879, Boisbaudran separated a rare earth oxide called samaria (samarium oxide) from the didymia fraction obtained from the mineral samarskite. Soon after that in 1885, Baron Auer von Welsbach isolated two other rare earths from didymia. He named them as praseodymia (green twin) and neodymia (new twin) after their source didymia (twin). The name praseodymium finally was assigned to this new element, derived from the two Greek words, prasios meaning green and didymos meaning twin. 

The discovery of samarium is credited to Boisbaudran, who in 1879 separated its oxide, samaria from Mosander s didymia, the mixture of rare earth oxides from which cerium and lanthanum were isolated earher. Demarcay in 1901 first identified samaria to be a mixture of samarium and europium oxides. The element got its name from its mineral, samarskite. The mineral, in turn, was named in honor of the Russian mine official Col. Samarki. 

The element was discovered in 1843 by Carl Gustav Mosander. He determined that the oxide, known as yttria, was actually a mixture of at least three rare earths which he named as yttria—a colorless oxide, erbia— a yellow oxide, and terbia— a rose-colored earth. Mosander separated these three oxides by fractional precipitation with ammonium hydroxide. Pure terbia was prepared by Urbain in 1905. The element was named terbium for its oxide, terbia, which was named after the Swedish town, Ytterby. 

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