Metaboric acid

Metaboric acid
Names
	IUPAC name Oxoborinic acid
	Other names Metaboric acid
Identifiers
CAS Number	13460-51-0 ;
3D model (JSmol)	Interactive image; Interactive image;
ChemSpider	22900 ;
ECHA InfoCard	100.033.313
EC Number	236-659-8;
Gmelin Reference	121829
PubChem CID	24492;
CompTox Dashboard (EPA)	DTXSID6065478 ;
	InChI InChI=1S/BHO2/c2-1-3/h2H Key: VGTPKLINSHNZRD-UHFFFAOYSA-N ;
	SMILES O=BO; OB1OB(O)OB(O)O1;
Properties
Chemical formula	B3H3O6
Molar mass	131.45 g·mol−1
Appearance	white solid
Density	1.784 g/cm3
Melting point	176 °C (349 °F; 449 K)
Acidity (pKa)	9.236
Conjugate base	Metaborate
Structure
Coordination geometry	trigonal at B
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P305+P351+P338
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Metaboric acid is the name for a family of inorganic compounds with the same empirical formula HBO₂ that differ in their molecular structure. They are colourless water-soluble solids formed by the dehydration or decomposition of boric acid.

Metaboric acid is formally the parent acid of the metaborate anions.