Pyrophosphoric acid

An inorganic compound, H4O7P2, 177.973 g/mol. Melting point 61 °C, as published.

verified recordInorganic compound1 measured properties

Identifiers

Molecular formula: H₄O₇P₂
Molecular weight: 177.973 g/mol
Exact mass: 177.943226 g/mol
IUPAC name: phosphono dihydrogen phosphate
SMILES: O=P(O)(O)OP(=O)(O)O
InChI: InChI=1S/H4O7P2/c1-8(2,3)7-9(4,5)6/h(H2,1,2,3)(H2,4,5,6)
InChIKey: XPPKVPWEQAFLFU-UHFFFAOYSA-N

Open in ReactionLens Use in reaction prediction

Measured properties

Published measurements, each with its source. Two readings of one property are both shown, in the units each used.

Melting Point: 61 °Cmeasured · DrugBank; 61 °Cmeasured · Human Metabolome Database (HMDB)

Calculated properties

Derived from the structure, not from a sample; kept apart from the measurements above.

Molecular weight: 177.98 g/molcalculated · reference compound database; Average mass of one molecule, from reference compound database.
Exact mass: 177.94322646 Dacalculated · reference compound database; Mass of the most common isotopic form.
XLogP3: -3.2calculated · reference compound database; Estimated oil/water partition, computed by reference compound database.
Polar surface area: 124 Å²calculated · reference compound database; Polar surface area as computed by reference compound database.
Complexity: 147calculated · reference compound database; A rough measure of how intricate the structure is.
H-bond donors: 4calculated · reference compound database
H-bond acceptors: 7calculated · reference compound database
logP: -0.8116calculated · chemistry engine; Estimated preference for oil over water. Higher means more oil-like.
Topological polar surface area: 124.29 Å²calculated · chemistry engine; Surface area from polar atoms; relates to how easily a molecule crosses membranes.
H-bond donors: 4calculated · chemistry engine; Atoms that can donate a hydrogen bond.
H-bond acceptors: 3calculated · chemistry engine; Atoms that can accept a hydrogen bond.
Rotatable bonds: 2calculated · chemistry engine; Single bonds the molecule can freely twist around.
Molar refractivity: 25.1732 cm³/molcalculated · chemistry engine; Relates to the molecule's polarisability.
Fraction sp³ carbons: 0calculated · chemistry engine; Share of carbon atoms with tetrahedral bonding.
QED drug-likeness: 0.4071calculated · chemistry engine; Quantitative estimate of drug-likeness (0–1).

What it is made of

Elements

O Oxygen7 atoms · 62.9% by mass
P Phosphorus2 atoms · 34.8% by mass
H Hydrogen4 atoms · 2.3% by mass

Percentages are of the molecular weight above, worked out the same way the molar mass calculator does it.

Structure

Heavy atoms, hydrogen excluded: 9
Total atoms, hydrogen included: 13
Rings: 0
Aromatic rings: 0
Stereocentres: 0
Formal charge: 0

Functional groups

Phosphate
A phosphorus centre bonded to four oxygens.

Matched by structural pattern, not by a measurement.

The molecule in three dimensions

Rotate and inspect the atoms. Loaded only when you ask, so the page stays light.

The drawing above is a diagram of what is bonded to what. A molecule is not flat, and the model here is one low-energy shape generated from the connectivity — useful for seeing which groups can reach each other, and not a measured structure. A real sample is a population of conformations, interconverting.

Reactions it appears in

No documented reaction with a written procedure and a source involves Pyrophosphoric acid yet.

Other names for it

The systematic name on this record is phosphono dihydrogen phosphate.

The sources also call it Diphosphoric acid, phosphono dihydrogen phosphate, (phosphonooxy)phosphonic acid, 4E862E7GRQ, H4P2O7, CHEBI:29888, DTXSID4075035, RefChem:55955, DTXCID4037118, hydron;phosphonato phosphate, Diphosphorsaeure.

Structurally related

Nothing structurally close to Pyrophosphoric acid has a page here yet.

Where these values came from

reference compound database1023
compound record
chemistry engine
structure perception

compound record.

What this page does not claim

Identifiers are copied from the source record, measured values are reported as published, and calculated values are marked as calculated. Nothing here is a hazard, purity or handling assessment — how the library is checked.