# Potassium pyrophosphate

**CAS:** 7320-34-5  
**PubChem CID:** [23740](https://pubchem.ncbi.nlm.nih.gov/compound/23740)  
**Molecular formula:** K₄O₇P₂  
**Molar mass:** 330.34 g/mol  
**IUPAC:** tetrapotassium;phosphonato phosphate  
**SMILES:** `[O-]P(=O)([O-])OP(=O)([O-])[O-].[K+].[K+].[K+].[K+]`  
**InChIKey:** `RYCLIXPGLDDLTM-UHFFFAOYSA-J`  
**InChI:** `InChI=1S/4K.H4O7P2/c;;;;1-8(2,3)7-9(4,5)6/h;;;;(H2,1,2,3)(H2,4,5,6)/q4*+1;/p-4`  

## Physicochemical properties

| Parameter | Value |
|---|---|
| PSA | 136 Ų |
| Hydrogen bond donors | 0 |
| Hydrogen bond acceptors | 7 |
| Rotatable bonds | 0 |
| Heavy atoms | 13 |

## 3D structure

The molecule contains 13 atoms connected by 8 chemical bonds. Interactive 3D model available at: https://molgod.org/molecule/7320-34-5/

## Synonyms

- Potassium pyrophosphate
- 7320-34-5
- Potassium diphosphate
- TKPP
- TETRAPOTASSIUM PYROPHOSPHATE
- Diphosphoric acid, tetrapotassium salt
- Tetrapotassium diphosphorate
- Pyrophosphoric acid, tetrapotassium salt
- B9W4019H5G
- RefChem:897424

## Data sources

- [PubChem CID 23740](https://pubchem.ncbi.nlm.nih.gov/compound/23740)
- [Wikidata](https://www.wikidata.org/wiki/Q2575439)
- [NIST WebBook](https://webbook.nist.gov/cgi/cbook.cgi?ID=7320-34-5)
- [ChEMBL](https://www.ebi.ac.uk/chembl/g/#search_results/all/query=7320-34-5)

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*Last updated: 2026-10-17 · Generator: MOL-GOD v3.12.33*