Trisodium pentaborate is a salt that can form as a monohydrate with formula Na3B5O8(OH)2·H2O, which contains the anion dihydroxydopentaborate [B5O8(OH)2]3−.[1]

Trisodium pentaborate
Identifiers
Properties
B5H2Na3O10
Molar mass 285.03 g·mol−1
Appearance Transparent crystal
Soluble
Structure
Orthorhombic
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Its formula may be incorrectly given as Na3B5O8·2H2O, or as 3Na2O5B2O3·4H2O. It may also be called simply sodium pentaborate,[1] but this name is more properly reserved for the compound with elemental formula Na2O·5B2O3·nH2O.

Structure edit

Trisodium pentaborate monohydrate crystallizes as thin plates in the orthorhombic crystal system, with symmetry group Pbca and cell parameters a = 880.4 pm, b = 1837.1 pm, c = 1092.4 pm, formulas per cell Z = 8.[1]

References edit

  1. ^ a b c Silvio Menchetti and Cesare Sabelli (1977): "The crystal structure of synthetic sodium pentaborate monohydrate". Acta Crystallographica Section B, volume B33, pages 3730-3733. doi:10.1107/S0567740877011959