Radium

Gives a red flame when burned [3].

Radium blackens when exposed to air. The reaction is believed to be the formation of the nitride [3]

3 Ra(s) + N₂(g) Ra₃N₂(s)

Radium decomposes in water. The reaction is less volatile than the corresponding reaction for barium [3]

Ra(s) + 2 H₂O(l) Ra(OH)₂(aq) + H₂(g).