Radium barium ratio

Radium is obtained from pitchblende, UgOg, in which it is formed by the disintegration of (p. 15), the equilibrium ratio being 3.4 x The sulphate is co-precipitated with BaS04 when BaClg is added to a sulphuric acid extract of the ore. After boiling with NaOH to remove lead, the sulphates are converted to carbonates by sodium carbonate fusion and dissolved in HCl to the chlorides. Fractional crystallisation of these removes much of the barium the final separation is effected by the same means after conversion to bromides. 

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