RADIUS

The radius is a chemical element of the periodic table. His symbol is Ra and his atomic number is 88. It is of white color, but it turns black with the exhibition to the air. The radius is an alcalinotérreo who is to level of traces in mines of uranium. It is extremely radioactive. When it is mixed by beryllium, it is a source of neutrons for physical experiments. Former it was used in luminescent paintings for clocks and other instruments. The radius (of the Latin radius, I border) was discovered in 1898 by Marie Curie and his husband Pierre in a variety of uraninita of the north of Bohemia.
While they were studying the mineral, the Curie withdrew the uranium from him and thought that the remaining material still was radioactive. Then they produced a radioactive mixture done principally of barium that was giving a red brilliant color of flame and spectral lines that had not received documents previously. In 1902 the radius was isolated by Curie and Andre Debierne in his pure metal by means of the electrolysis of a solution of pure chloride of radio using a cathode of mercury and falling in an atmosphere of hydrogen.

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