Preparation
Radium hydroxide may be prepared
by the reaction of BeO added to water. The reaction is
violent with evolution of considerable heat:
RaO+H2O→Ra(OH)2
It may also be prepared by reacting the nitrate with
NaOH in solution. There is no record of this salt actually
having been prepared. However, it is expected that
beryllium hydroxide is soluble so that the solution needs
to be evaporated at a low temperature (with vacuum) in
the presence of ethanol to crystallize the salt,
Be(OH)2·8H2O. The crystals are then washed in cold
ethanol to remove traces of sodium ions and then dried.
The crystals are strongly absorbent of carbon dioxide
from the air, forming the carbonate as an end-product.