Phosphorous acid

HCID 107909CAS 10294-56-1
Substructure searchFind similar structures

Basic information

Standard SMILES
OP(O)O
InChIKey
OJMIONKXNSYLSR-UHFFFAOYSA-N
Molecular formula
H3O3P
Average molar mass
81.996 g/mol
Monoisotopic mass
81.98198059

Overview

Phosphorous acid is a phosphorus oxoacid. It is a conjugate acid of a dihydrogenphosphite. It is a tautomer of a phosphonic acid.

Names & identifiers

Preferred name
Phosphorous acid
IUPAC
phosphorous acid
English name
Orthophosphorus acid
Molecular formula
H3O3P
Molecular weight
82

Names & synonyms

Phosphorous acid10294-56-1Orthophosphorus acidDTXSID7035511CHEBI:36361RefChem:1095536DTXCID5015511233-663-135V6A8JW8EDihydroxyphosphine oxideTrihydroxyphosphinePhosphorane, trihydroxy-
Show more names
Phosphorous acid 50% aqueous solutionPhosphorou acidAD Orthophosphorus acidOrthophosphorus acid ISO 9001：2015 REACH
Orthophosphorous acidCaswell No. 663ItrioxophosphatePhophorous acidtrioxidophosphatePhosphorous-acid-EINECS 233-663-1UN2834

Database identifiers

CAS
10294-56-1、14901-63-4
PubChem CID
107909
DTXSID
DTXSID7035511
ChEBI
CHEBI:36361
EC Number
233-663-1
Nikkaji
J95.182J

Properties

Computed structural properties

XLogP
-1.5
Topological polar surface area
60.7 Ų
Hydrogen bond donors
3
Hydrogen bond acceptors
3
Rotatable bonds
0
Heavy atoms
4

Experimental & physicochemical properties

Physical Description · 2 items

Liquid

Solid

Physicochemical properties

pka
2.22 · 2.22±0.10(Predicted)
InChI
InChI=1S/H3O3P/c1-4(2)3/h1-3H
InChIKey
OJMIONKXNSYLSR-UHFFFAOYSA-N
SMILES
P(O)(O)O
CAS DataBase Reference
10294 · 10294-56-1
FDA UNII
35 V6A8JW8E · 35V6A8JW8E

Safety & regulation

GHS classification

GHS Classification · 6 items

Danger

H302: Harmful if swallowed [Warning Acute toxicity, oral]

P260, P264, P270, P280, P301+P317, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P330, P363, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for 0.3% (2 of 719) of reports.

Danger

H302 (89.3%): Harmful if swallowed [Warning Acute toxicity, oral]

Hazard information

Regulatory Information · 3 items

Chemical: Phosphorous acid

Phosphorous acid is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Phosphorous acid are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Phosphorous acid: Does not have an individual approval but may be used under an appropriate group standard

Other Safety InformationIMAP assessments - Phosphorous acid: Environment tier I assessment
Fire Hazards· Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
Health Hazards· TOXIC and/or CORROSIVE; inhalation, ingestion or skin contact with material may cause severe injury or death.
DOT ID and Guide2834 154
EPA Safer ChemicalChemical: Phosphorous acid

Safety & protection

Accidental Release Measures · 2 items

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

First AidGeneral First Aid:
Exposure Control and Personal Protection· Wear positive pressure self-contained breathing apparatus (SCBA).
Isolation and EvacuationImmediate precautionary measure
Protective Action Criteria (PAC) · 3 items

3.0 [mg/m3]

30 [mg/m3]

150 [mg/m3]

Emergency Response Planning GuidelinesSmall Fire

Safety data

tsca
TSCA listed
ridadr
UN 2834
risk_code
22-35
Signal word
Danger
Symbol(GHS)
GHS05,GHS07
hazard_code
Xn,C

Chemistry & industry

Uses & manufacturing

U.S. Production2023: 5,000,000 - <10,000,000 lb
Consumer UsesLubricating agent
Industry UsesStabilizing agent
Use Classification · 2 items

EPA Safer Chemical Functional Use Classes -> Oxidants and Oxidant Stabilizers

Safer Chemical Classes -> Yellow triangle - The chemical has met Safer Choice Criteria for its functional ingredient-class, but has some hazard profile issues

General Manufacturing Information · 2 items

Not Known or Reasonably Ascertainable

Phosphorous acid: ACTIVE

Applications

UsesPhosphorous acid is a reducer in chemical reactions and a raw material in the making of phosphorous acid salts. A plant defoliant.

Upstream & downstream products

Upstream raw materials

Suppliers50 total

国药集团化学试剂有限公司86-21-63210123 · [email protected]
山东瑞博恩新材料科技有限公司15064961989 · [email protected]
南通润丰石油化工有限公司66017690 19952660367 · [email protected]
山东欣合新材料有限公司15665828542 15662672320 · [email protected]
武汉欣扬瑞和化学科技有限公司18171205315; 18171205315 · [email protected]
Additional notes · 1 item

DefinitionA white crystalline solid. It is a monobasic acid forming the anion H2PO2- in water. The sodium salt, and hence the acid, can be prepared by heating yellow phosphorus with sodium hydroxide solution. The free acid and its salts are powerful reducing agents.

Related reactions

196 records
New reaction record

Linked notes

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