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Chemical substance record

Acetaldehyde

75-07-0C2H4O44.053 g/mol

The aldehyde formed from acetic acid by reduction of the carboxy group. It is the most abundant carcinogen in tobacco smoke. — ChEBI

Safety references

Safety documents & references

2 indexed references
US · NIOSH

Occupational chemical safety guide

Acetaldehyde

Read official guide
JP · NITE

Government GHS classification

H27-B-034/C-070B_P · FY2015

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 number75-07-0ChEBI ↗
Molecular formulaC2H4OChEBI ↗
Molar mass44.053 g/molChEBI ↗
Monoisotopic mass44.02621 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:15343ChEBI ↗

Cross-source molecular data

PubChem
Molar mass44.05 g/molPubChem ↗
Exact mass44.026214747 DaPubChem ↗
Computed XLogP-0.3PubChem ↗
Topological polar surface area (Ų)17.1PubChem ↗
H-bond donors0PubChem ↗
H-bond acceptors1PubChem ↗
Rotatable bonds0PubChem ↗

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
acetaldehyde
acetaldehyde
IKHGUXGNUITLKF-UHFFFAOYSA-N
[H]C(C)=O
InChI=1S/C2H4O/c1-2-3/h2H,1H3

Classification & relationships

ChEBI ontology

Roles recorded in ChEBI

electron acceptormutagencarcinogenic agentteratogenic agentoxidising agentmouse metaboliteSaccharomyces cerevisiae metaboliteEscherichia coli metabolitehuman metaboliteEC 3.5.1.4 (amidase) inhibitor

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 · FY2015 source classification
Acetaldehyde · H27-B-034/C-070B_P
EndpointReported classification
Flammable liquidsCategory 1
Acute toxicity (Oral)Category 4
Acute toxicity (Dermal)Category 3
Acute toxicity (Inhalation: Vapours)Category 4
Serious eye damage/eye irritationCategory 2A
Skin sensitizationCategory 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
0.0226999 mol

Uses 44.053 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
C
Carbon · 2 atoms
54.53%
O
Oxygen · 1 atom
36.32%
H
Hydrogen · 4 atoms
9.15%

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:15343

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

NCBI PubChem · CID 177 · 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.