Trimagnesium phosphate describes inorganic compounds with formula Mg3(PO4)2.xH2O. They are magnesium acid salts of phosphoric acid, with varying amounts of water of crystallization: x = 0, 5, 8, 22.[2]
The octahydrate forms upon reaction of stoichiometric quantities of monomagnesium phosphate (tetrahydrate) with magnesium hydroxide.
- Mg(H2PO4)2•4H2O + 2 Mg(OH)2 → Mg3(PO4)2•8H2O
The octahydrate is found in nature as the mineral bobierrite.[3]
The anhydrous compound is obtained by heating the hydrates to 400 °C. It is isostructural with cobalt(II) phosphate. The metal ions occupy both octahedral (six-coordinate) and pentacoordinate sites in a 1:2 ratio.[4]
Safety
Magnesium phosphate tribasic is listed on the FDA's generally recognized as safe, or GRAS, list of substances.[5]
See also
References
- ^ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–188. ISBN 978-1138561632.
- ^ Klaus Schrödter; Gerhard Bettermann; Thomas Staffel; Friedrich Wahl; Thomas Klein; Thomas Hofmann (2008). "Phosphoric Acid and Phosphates". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_465.pub3. ISBN 978-3527306732. S2CID 94458523.
- ^ "magnesium phosphate - Compound Summary". Retrieved 29 May 2012.
- ^ Nord, A. G.; Stefanidis, T. (1983). "Structure of cobalt(II) phosphate Structure Refinements of Co3(PO4)2. A Note on the Reliability of Powder Diffraction Studies". Acta Chemica Scandinavica A. 37: 715–p721. doi:10.3891/acta.chem.scand.37a-0715.
- ^ "TRIMAGNESIUM PHOSPHATE". Retrieved 29 May 2012.