Radium peroxyphosphate has remained unknown
and no publications concerning this salt are available
in the scientific literature. This is not surprising in
view of the intense radioactivity of 226Ra. Like the other
alkaline earths, radium peroxyphosphates could be
prepared by both solid-state or solution methods. For
the monoperoxyphosphates, one would get RaHPO5
for the former method. The question of degree of hydration
remains unknown.
In the solution method, one could use the acid, H3PO5
or the potassium salt K2HPO5. Whether the solution
should be acidic or basic is not known. Like the other
alkaline earths, it is probably best to prepare the acid
in a nonaqueous solution like carbon tetrachloride and
then add the potassium compound for the basic
solution:
P2O5 + 2H2O2 +H2O ? 2H3PO5
2H3PO5 + KOH ? K2HPO5
To either of these is added the radium compound to
form the monoperoxyphosphate:
Ra(OH)2 + K2PO50RaHPO5 +H2O
To prepare radium diperoxy compounds, the potassium
monoperoxyphosphate compound is transformed
to the diperoxyphosphate compound, in a nonaqueous
solution at low temperature:
K2HPO5 + P2O5 ? K2P2O8
