Preparation
There
is no record of either of these salts ever having been prepared, although they could be made by several
methods. The best one would be to react metaphosphoric
acid and the hydroxide, oxide or carbonate of
radium in the solid state:
RaCO3 + HPO3 + heat Ra(PO3)2 +H2O + CO2
The best temperature to use is about 700°C. It has no
CAS number. The molecular weight is expected to be
383.9663 g/mol. This compound can also be prepared
by the aqueous reactions:
NaPO3 (aq) + RaCl2 (aq) Ra(PO3)2 (solid) + NaCl (aq)
or
Ra(OH)2 (solid) + 2HPO3 (aq) Ra(PO3)2 (solid)
+ 2H2O
Whether hydrates form remains unknown at this
date. The only reference in the scientific literature
concerns the removal of radioactive
226Ra from drinking
water by the addition of sodium polyphosphate.
Radium polyphosphate is sufficiently insoluble so that
all of the radium polyphosphate could be filtered out
and subjected to proper disposal.
