Dmitri Mendeleev

Dmitri Ivanovich Mendeléiev

(Tobolsk, Russia now, 1834, St. Petersburg, 1907) Russian Chemical. His family, which was the youngest of seventeen siblings, was forced to migrate from Siberia toRussia because of the blindness of the father and the loss of the family business following a fire. Its origin Siberian closed the doors of the universities of Moscow and St. Petersburg, which was formedby the Pedagogical Institute of the latter city.
He later moved to Germany for further studies in Heidelberg, where he met leading chemists of the time. On his return to Russia he was appointedprofessor at the University of St. Petersburg (1864) and university professor (1867), a position he would be forced to leave in 1890 for political reasons, although he was given the address of the Officeweights and Measures (1893).
His work includes studies of the thermal expansion of liquids, the discovery of the critical point, the study of the deviations of real gases from what stated in the lawof Boyle and a more precise formulation of the equation status. In the practical field highlight his great contributions to the industries of soda and oil from Russia.
However, his greatestachievement was the establishment of research called periodic system of chemical elements, or periodic table by which culminated a definitive classification of these elements (1869) and opened the way for thegreat progress made by the chemical the twentieth century.


What are lanthanoids?
The fifteen elements from lanthanum, La , to lutetium, Lu, are lanthanoids. Ln may be used as a general symbolfor the lanthanoid elements.
Although lanthanoids, scandium, Sc, and yttrium, Y, are sometimes called rare earth elements, they are relatively abundant in the earth’s crust. With the exception ofpromethium, Pm, which does form a stable isotope, even the least abundant thulium, Tm, and lutetium, Lu, are as abundant as iodine. Because lanthanoids have very similar properties and are difficult to...