Happy birthday periodic table!

150th anniversary of the periodic table

Russian chemist Dmitri Mendeleev presents the first periodic table of the elements to the Russian Chemical Society on March 6, 1869.

An "alternative" periodic table

Tabla Periodica.jpg

In the fig., we can see the new periodic table of elements, by the European Chemical Society. The size of each box is proportional to the availability of the element.

A little history here
Thus, on 6 March 1869 the Russian scholar officially presents the periodic table of elements within the report entitled "The interdependence between the properties of atomic weights of the elements", proposed to the Russian Chemical Society which he himself founded a few months before with other scientists. In the table, all the 63 known elements are placed, while three empty spaces are left for the still unknown elements.

In fact, the importance of its predictions is recognized after the discovery of germanium, gallium and scandium, which occupy the places left empty inside the table, and which have exactly the same physical properties that their position in it provided.