Radium hydroxide

Radium hydroxide is an inorganic compound of radium, hydrogen, and oxygen with the chemical formula Ra(OH)2. Stability constant of aqueous RaOH+ ion pair at zero ionic strength is equal to 5.

Synthesis

 * A reaction of radium metal with water:


 * Ra + 2H2O -> Ra(HO)2 + H2


 * The reaction of radium oxide and water can also generate radium hydroxide, and the reaction releases a lot of heat:


 * RaO + H2O -> Ra(HO)2


 * The compound can also be prepared by reacting radium nitrate with NaOH in solution.

Physical properties
Radium hydroxide forms colorless crystals that dissolve in water better than does barium hydroxide, and has more basic properties.

The compound forms a hydrate of the composition Ra(OH)2*8H2O.

Radium hydroxide is a caustic, toxic, and corrosive substance. It is significantly more toxic than barium hydroxide (Ba(OH)2) and strontium hydroxide (Sr(OH)2).