Lecoq, Paul-Emile

Samarium (Sm, [Xe]4/66.r). Name and symbol after the mineral samarskite. Discovered (1879) by Paul Emile Lecoq de Boisbaudran. 

Dysprosium - the atomic number is 66 and the chemical symbol is Dy. The name derives from the Greek dysprositos for hard to get at , due to the difficulty in separating this rare earth element from a holmium mineral in which it was found. Discovery was first claimed by the Swiss chemist Marc Delafontaine in the mineral samarskite in 1878 and he called it philippia. Philippia was subsequently found to be a mixture of terbium and erbium. Dysprosium was later discovered in a holmium sample by the French chemist Paul-Emile Lecoq de Boisbaudron in 1886, who was then credited with the discovery. It was first isolated by the French chemist George Urbain in 1906. 

Gadolinium - the atomic number is 64 and the chemical symbol is Gd. The name derives from the mineral gadolinite, in which it was found, and which had been named for the Finnish rare earth chemist Johan Gadolin . It was discovered by the Swiss chemist Jean-Charles Galissard de Marignac in 1886, who produced a white oxide he called Y in a samarskite mineral. In 1886, the French chemist Paul-Emile Lecoq de Boisbaudran gave the name gadolinium to Y . 

Gallium - the atomic number is 31 and the chemical symbol is Ga. The name derives from the Latin gallia for France or perhaps from the Latin gallus for le coq or cock , since it was discovered in zinc blende by the French chemist Paul-Emile Lecoq de Boisbaudan in 1875. It was first isolated in 1878 by Lecoq de Boisbaudran and the French chemist Emile-Clement Jungflesch. This element had previously been predicted as eka-aluminum by Mendeleev, along with its properties and its location in the Periodic Table. 

Dysprosium was first discovered in 1886 by the chemist, Paul-Emile Lecoq de Boisbaudran (1838-1912) as he analyzed a sample of the newly discovered erbium oxide (element 68). Boisbaudran was able to separate erbium oxide from a small sample of a new oxide of a metal. He identified this new element as element 66 on the periodic table and called it dispro-... 

French chemists Jean de Marignac and Paul-Emile Lecoq de Boisbaudran... 

Ramsay, W, Paul Emile (dit Francois) Lecoq de Boisbaudran, J. Chem... 

In 1879 Paul-Emile Lecoq, gallium s discoverer, announced that there was another element contaminating didymium, which he called samarium. A year later Charles Galissard de Marignac in... 

Paris by the French scientist Paul-Emile Lecoq de Boisbaudran. Its isolation was made possible by the development of ion-exchange separation in the 1950s. Dysprosium belongs to a series of elements called rare earths, lanthanides, or 4f elements. The occurrence of dysprosium is low 4.5 ppm (parts per million), that is, 4.5 grams per metric ton in Earth s crust, and 2 x 10 7 ppm in seawater. Two minerals that contain many of the rare earth elements (including dysprosium) are commercially important mon-azite (found in Australia, Brazil, India, Malaysia, and South Africa) and bast-nasite (found in China and the United States). As a metal, dysprosium is reactive and yields easily oxides or salts of its triply oxidized form (Dy3+ ion). 

Gallium was discovered in 1875 by Paul-Emile Lecoq de Boisbaudran at Paris, France, when he examined the spectrum of a zinc sulfide ore from the Pyrenees and saw a faint blue-violet line which told him a new element was present. Its existence had already been predicted six years earlier by the Russian chemist Dimitri Mendeleyev, the man who drew up the first periodic table and saw there was a missing element below aluminium in his group III. 

Over a period of more than a cenmry, chemists argued about the composition of yttria. Eventually, chemists agreed that yttria is actually a combination of nine different elements that had not been seen before. One of those elements is dysprosium. Dysprosium was finally proved to be a new element in 1886 by French chemist Paul-emile Lecoq de Bois-baudran (1838—1912). The name chosen for this new element comes from the Greek word meaning difficult to obtain. ... 

Using Mendeleev s periodic law, the element was soon found. It was discovered by French chemist Paul-emile Lecoq de Boisbaudran in 1875. 

The discovery of samarium grew out of this kind of frustration. In 1880, French chemist Paul-emile Lecoq de Boisbaudran (1838—1912) was studying a substance known as didymium. Earlier chemists believed didymium might be a new element. Boisbaudran said that at least two new elements were present in didymium. 

Paul-Emile Lecoq de Boisbaudran discovers gallium. 

The element is named using the Latin name Gallia, for France. It was predicted and described in 1863 by Mendeleev as eka-aluminum and discovered in 1875 by Paul Emile (Francois) Lecoq de Boisbaudran (1838-1912) using spectroscopic analysis. He isolated elemental gallium the same year. The... 

Table 1. Eka aluminum was predicted by Mendeleev and discovered by the French chemist Paul-Emile Lecoq de Boisbaudran in 1875 and named gallium.

Other chemists began to make use of this new tool. One of them was the French chemist Paul Emile Lecoq de Boisbaudran (1838-1912), who spent fifteen years studying the minerals of his native Pyrenees by means of the spectroscope. In 1875, he tracked down some unknown lines and found a new element in zinc ore. He named it gallium, for Gaul (France). 

Paul Emile Lecoq de Boisboudran 1838-1912 Samarium, 1879, dysprosium, 1886, gadolinium, 1886 France... 

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