Ammonium pentaborate

Ammonium pentaborate
Names
	IUPAC name azanium;(7-oxido-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonan-3-yl)oxy-oxoborane
Identifiers
CAS Number	12007-89-5 ; tetrahydrate: 12046-04-7; octahydrate: 12046-03-6;
3D model (JSmol)	Interactive image; tetrahydrate: Interactive image; octahydrate: Interactive image;
ChemSpider	52085560;
EC Number	234-521-1;
PubChem CID	131634794;
UNII	E9ND2KN062;
	InChI InChI=1S/B5O8.H3N/c6-1-8-3-11-4-9-2(7)10-5(12-3)13-4;/h;1H3/q-1;/p+1 Key: OEAWHXRHGIIPBU-UHFFFAOYSA-O;
	SMILES B(=O)OB1OB2OB(OB(O2)O1)[O-].[NH4+]; tetrahydrate: B(=O)OB1OB2OB(OB(O2)O1)[O-].[NH4+].O.O.O.O; octahydrate: B(=O)OB1OB2OB(OB(O2)O1)[O-].[NH4+].O.O.O.O.O.O.O.O;
Properties
Chemical formula	B5H4NO8
Molar mass	200.08 g·mol−1
Appearance	white crystals
Density	g/cm3 (hydrate)
Solubility in water	soluble
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Ammonium pentaborate is a chemical compound with the chemical formula NH₄B₅O₈.^[1]^[2]

Synthesis

The compound can be prepared by a controlled reaction of ammonia, boric acid, and water.^[3]^[4]

The compound forms white crystals soluble in water.^[5]

Ammonium pentaborate forms a tetrahydrate H₄N · B₅O₈ · 4H₂O^[6] and an octahydrate H₄N · B₅O₈ · 8H₂O.^[7]

The compound is used to inhibit heat, flame, and corrosion in a variety of industrial applications.^[8]