Description
Beryllium pyrosulfate is not stable in aqueous solution
and so must be prepared via a solid-state reaction.
It would have the molecular formula of BeS
2O
7 and the molecular weight of 185.1401 g/mol. It could be
prepared by the reaction involving “fuming” sulfuric
acid (oleum) with beryllium sulfate:
[Be(OH)]2SO4+(H2SO4)n ? 2BeS2O7+(n+2) H2O
The [Be(OH)]
2SO
4 salt is added to the oleum and
allowed to dissolve in an excess of acid. The acid is
heated to 150–175°C to drive off the water. This is
an equivalent of using H
2S
2O
7. The solution is allowed
to equilibrate and crystals of the anhydrous salt
appear. These are separated and allowed to dry. Beryllium
disulfate is stable and may be heated to a red
heat before it begins to decompose to the sulfate
and SO
3.
