Discovery of radium Continued Yield: 8 kg: Activity: 60 times more active than uraniu Precipitate(Ac) Supematant: Precipitate with sodium carbonate (Carbonates of alkali earth, Ra, Ba, etc. Wash the precipitate convert carbonates to chloride solution Fractional crystallisation(FC)with pure water Crystals enriched in Ra by Supernatant(B) a factor of five(5). Repeat Crystals(A) FC with both a and B Evaporate to FC dryness, FC 2005-9-13 NECPKU