How to extract radium? What is radium?

A chemical element. Chemical symbol Ra, atomic number 88, atomic weight 226.0254, belongs to IIA group in the periodic table, is a member of alkaline earth metal and a natural radioactive element. 1898 m. Curie and p. Curie separated radium bromide from the slag after extracting uranium from pitchblende, and 19 10 made metal radium by electrolysis of radium chloride. Its English name comes from the Latin radius, which means "ray". The content of radium in the crust is 1× 10-9%. It has been found that isotopes with mass numbers of 206 ~ 230 are all artificially synthesized except for radium 223, radium 224, radium 226 and radium 228, which are natural radioactive isotopes. Radium exists in all uranium mines, and every 2.8 tons of uranium contains 1 gram of radium.

Radium is a silvery white metal with a melting point of 700℃, a boiling point lower than 1 140℃ and a density of about 5g/cm3. Radium is the most active alkaline earth metal, which reacts rapidly with nitrogen and oxygen in air to form nitrides and oxides, and reacts violently with water to form radium hydroxide and hydrogen. The outermost electron shell of radium has two electrons, and the oxidation state is +2, and only +2 valence compounds are formed. Radium salts and corresponding barium salts are isomorphic compounds with similar chemical properties. Radium chloride, radium bromide and radium nitrate are all soluble in water, while radium sulfate, radium carbonate and radium chromate are insoluble in water. Radium is highly toxic and can be concentrated in bones instead of calcium in human body. Acute poisoning can cause bone marrow damage and serious damage to hematopoietic tissue, while chronic poisoning can cause osteoma and leukemia. Radium is a by-product of uranium production. When leaching uranium from uranium ore with sulfuric acid, radium exists in slag in the form of sulfate, and then it is converted into radium chloride. Pure radium salt can be obtained by fractional crystallization with barium salt as carrier. Metal radium is made from electrolytic radium chloride. Radium and its decay products emit gamma rays, which can destroy malignant tissues in the human body, so radium needles can cure cancer.