Gives a red flame when burned .
Reaction of radium with air
Radium blackens when exposed to air. The reaction is believed to be the formation of the nitride 
3 Ra(s) + N2(g) Ra3N2(s)
Reaction of radium with water
Radium decomposes in water. The reaction is less volatile than the corresponding reaction for barium 
Ra(s) + 2 H2O(l) Ra(OH)2(aq) + H2(g).