Beryllium Arsenite could be prepared by the solidstate
reactions of the oxide and solid arsenous acid:
BeO +H3AsO3 + heat ? BeHAsO3 +H2O
At a 2:1 ratio and a pH of 13.5, one would expect to
obtain Be3(AsO3)2. However, there is no record of this
having been attempted. Attempts to prepare definite compounds of beryllium with arsenious acid in aqueous
solution have not been successful. When beryllium
hydroxide is precipitated from solutions containing
arsenious oxide, much of the latter is adsorbed but
a product has never been isolated and identified. The
literature is devoid of any references and the only citations
are dated in the 1860–1880s. Perhaps this is due
to the fact that beryllium cations in aqueous solution
are dominated by hydroxy groups which attach themselves
to Be2+ to form species like Be(OH)+. These do
not react the same in solution as the other alkaline
earths do.