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Chemical substance record

Potassium

7440-09-7K39.098 g/mol
ElementChEBI source record

Potassium is indexed in ChEBI under CHEBI:26216, with the reported formula K. Use the source record and structural identifiers below to confirm the material you need. — ChEBI

Safety references

Safety documents & references

1 indexed references
JP · NITE

Government GHS classification

H30-C-057-MOE · FY2018

View classification

Find a product-specific SDS

Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.

Identity & molecular properties

Source-linked values
CAS number7440-09-7ChEBI ↗
Molecular formulaKChEBI ↗
Molar mass39.098 g/molChEBI ↗
Monoisotopic mass38.96371 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:26216ChEBI ↗

Cross-source molecular data

PubChem
Molar mass39.0983 g/molPubChem ↗
Exact mass38.96370648 DaPubChem ↗

PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.

Names & structural identifiers

Copy any identifier
potassium atom
potassium
ZLMJMSJWJFRBEC-UHFFFAOYSA-N
[K]
InChI=1S/K

Names & synonyms

potassium

Names are supplied by ChEBI. Trade names and related synonyms may describe a broader product context.

Classification & relationships

ChEBI ontology

Roles recorded in ChEBI

macronutrientantihypertensive agentanti-arrhythmia drugSaccharomyces cerevisiae metabolite

Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.

Safety classification · Japan

NITE / Japanese government
Japan · FY2018 source classification
Potassium · H30-C-057-MOE

Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.

Read the original NITE classification

Mass ↔ amount of substance

Calculated from sourced mass
Equivalent amount
0.0255768 mol

Uses 39.098 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
K
Potassium · 1 atom
100.00%

Calculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.

Research & patent references

Selected source associations

Explore literature using this exact identifier.

Sources & record history

Checked 27 Sep 2026
EMBL-EBI ChEBI · CHEBI:26216

Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0

NCBI PubChem · CID 5462222 · retrieved 2026-09-27

PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.