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Chemical substance record

Copper(II) sulfate pentahydrate

7758-99-8Cu.5H2O.O4S249.684 g/mol
Salt and Compound WithChEBI source record

The pentahydrate of copper(2+) sulfate. A bright blue crystalline solid. — ChEBI

Safety references

Safety documents & references

1 indexed references
JP · NITE

Government GHS classification

R06-C-107-JNIOSH · FY2024

View classification

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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 number7758-99-8ChEBI ↗
Molecular formulaCu.5H2O.O4SChEBI ↗
Molar mass249.684 g/molChEBI ↗
Monoisotopic mass248.93415 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:31440ChEBI ↗

Cross-source molecular data

PubChem
Molar mass249.69 g/molPubChem ↗
Exact mass248.934150 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
copper(II) sulfate pentahydrate
copper(2+) sulfate pentahydrate
JZCCFEFSEZPSOG-UHFFFAOYSA-L
O=S(=O)([O-])[O-].[Cu+2].[H]O[H].[H]O[H].[H]O[H].[H]O[H].[H]O[H]
InChI=1S/Cu.H2O4S.5H2O/c;1-5(2,3)4;;;;;/h;(H2,1,2,3,4);5*1H2/q+2;;;;;;/p-2

Names & synonyms

copper(2+) sulfate pentahydratecopper(2+) sulfate--water (1/5)

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

Classification & relationships

ChEBI ontology

Safety classification · Japan

NITE / Japanese government
Japan · FY2024 source classification
Copper(II) sulfate pentahydrate · R06-C-107-JNIOSH
EndpointReported classification
Serious eye damage/eye irritationCategory 1

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
0.00400506 mol

Uses 249.684 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
Cu
Copper · 5 atoms
73.58%
O
Oxygen · 5 atoms
18.52%
S
Sulfur · 1 atom
7.43%
H
Hydrogen · 2 atoms
0.47%

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

Sources & record history

Checked 27 Sep 2026
EMBL-EBI ChEBI · CHEBI:31440

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

NCBI PubChem · CID 24463 · 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.