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Chemical substance record

Arsenic trichloride

7784-34-1AsCl3181.281 g/mol

A arsenic molecular entity that consists of a single arsenic atom bearing three chloro substituents. — ChEBI

Safety references

Safety documents & references

1 indexed references
JP · NITE

Government GHS classification

20A2342 · FY2008

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 number7784-34-1ChEBI ↗
Molecular formulaAsCl3ChEBI ↗
Molar mass181.281 g/molChEBI ↗
Monoisotopic mass179.82815 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:63952ChEBI ↗

Cross-source molecular data

PubChem
Molar mass181.28 g/molPubChem ↗
Exact mass179.828153 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
arsenic trichloride
arsenous chloride
OEYOHULQRFXULB-UHFFFAOYSA-N
Cl[As](Cl)Cl
InChI=1S/AsCl3/c2-1(3)4

Names & synonyms

arsenous chloride

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

Classification & relationships

ChEBI ontology

Roles recorded in ChEBI

genotoxin

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 · FY2008 source classification
Arsenic trichloride · 20A2342
EndpointReported classification
Serious eye damage/eye irritationCategory 2
Germ cell mutagenicityCategory 2
CarcinogenicityCategory 1A
Reproductive toxicityCategory 2
Specific target organ toxicity - Single exposureCategory 1 (digestive system, circulatory system, nervous system, blood system, respiratory system, skin, kidney, liver)
Specific target organ toxicity - Repeated exposureCategory 1 (digestive system, circulatory system, nervous system, kidney, liver, blood system, respiratory system, skin)

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
0.0055163 mol

Uses 181.281 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
Cl
Chlorine · 3 atoms
58.67%
As
Arsenic · 1 atom
41.33%

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:63952

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

NCBI PubChem · CID 24570 · 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.