Radium chloride radium chloride is weakly paramagnetic with a magnetic susceptibility of 1.05. It also differs from barium chloride by the flame color, which is red as opposed to green for barium chloride. Radium chloride is still used for the initial stages of the separation of radium from barium during the extraction of radium from pitchblende. The large quantities of material involved (tonnes of ore for milligrams of radium) favour this less costly (but less efficient) method over those based on radium bromide or radium chromate (used for the later stages of the separation). It was also used in medicine to produce
Radium actinium hydroxide and thorium hydroxide: these three adjacent hydroxides may be separated by precipitating them with ammonia. Radium chloride (RaCl) is a colorless, luminous compound. It becomes yellow after some time due to self-damage by the alpha radiation given off by radium when it decays. Small amounts of barium impurities give the compound a rose color. It is soluble in water, though less so than barium chloride, and its solubility decreases with increasing concentration of hydrochloric acid. Crystallization from aqueous solution gives the dihydrate RaCl·2HO, isomorphous with its barium analog. Radium bromide (RaBr) is also a colorless, luminous compound. In