Melting point :73 °C
Boiling point :200 °C
Density :1.651 g/mL at 25 °C(lit.)
vapor pressure :0.001Pa at 20℃
Flash point :200°C
storage temp. :0-6°C
solubility :DMSO (Slightly), Methanol (Slightly), Water (Sparingly)
form :Crystals
pka :pK1 1.29; pK2 6.74(at 25℃)
Specific Gravity :1.651
color :White
PH :pKa1= 1.10, pKa2 = 6.33(25℃)
Water Solubility :SOLUBLE
Sensitive :Air Sensitive & Hygroscopic
Merck :14,7346
Stability :Stable. Incompatible with strong bases. Hygroscopic.
CAS DataBase Reference :13598-36-2(CAS DataBase Reference)
NIST Chemistry Reference :(HO)2HPO(13598-36-2)
EPA Substance Registry System :Phosphonic acid (13598-36-2)

Symbol(GHS):
Signal word:	Danger
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H290 May be corrosive to metals Corrosive to Metals Category 1 Warning P234, P390, P404 H302 Harmful if swallowed Acute toxicity,oral Category 4 Warning P264, P270, P301+P312, P330, P501 H314 Causes severe skin burns and eye damage Skin corrosion/irritation Category 1A, B, C Danger P260,P264, P280, P301+P330+ P331,P303+P361+P353, P363, P304+P340,P310, P321, P305+ P351+P338, P405,P501
Precautionary statements:	P234 Keep only in original container. P270 Do not eat, drink or smoke when using this product. P280 Wear protective gloves/protective clothing/eye protection/face protection. P301+P312 IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell. P303+P361+P353 IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.