Acetaldehyde

An aldehyde, C2H4O, 44.053 g/mol. Boiling point 20.8 °C, melting point -123.4 °C, as published. Appears in 1 documented reaction.

verified recordOrganic — aldehyde7 measured properties1 documented reactions

Identifiers

Molecular formula: C₂H₄O
Molecular weight: 44.053 g/mol
Exact mass: 44.026215 g/mol
IUPAC name: acetaldehyde
SMILES: CC=O
InChI: InChI=1S/C2H4O/c1-2-3/h2H,1H3
InChIKey: IKHGUXGNUITLKF-UHFFFAOYSA-N

Open in ReactionLens Use in reaction prediction

Measured properties

Published measurements, each with its source. Two readings of one property are both shown, in the units each used.

Boiling Point: 70 °F at 760 mmHg (NTP, 1992)measured · CAMEO Chemicals; 20.8 °Cmeasured · Hazardous Substances Data Bank (HSDB)
Melting Point: -190.3 °F (NTP, 1992)measured · CAMEO Chemicals; -123.4 °Cmeasured · Hazardous Substances Data Bank (HSDB)
Density: 0.78 at 68 °F (USCG, 1999) - Less dense than water; will floatmeasured · CAMEO Chemicals; 0.7834 g/cu cm at 18 °Cmeasured · Hazardous Substances Data Bank (HSDB)
Solubility: 0.1 to 1.0 mg/mL at 66 °F (NTP, 1992)measured · CAMEO Chemicals; Miscible with water /1X10+6 mg/L at 25 °C/measured · Hazardous Substances Data Bank (HSDB)
Vapor Pressure: 400 mmHg at 40.8 °F ; 760 mmHg at 68.4 °F (NTP, 1992)measured · CAMEO Chemicals; 902.0 [mmHg]measured · Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
LogP: log Kow = -0.34measured · Hazardous Substances Data Bank (HSDB); -0.34measured · Human Metabolome Database (HMDB)
Flash Point: -40 °F (NTP, 1992)measured · CAMEO Chemicals; -40 °C (-40 °F) - closed cupmeasured · Hazardous Substances Data Bank (HSDB)

Calculated properties

Derived from the structure, not from a sample; kept apart from the measurements above.

Molecular weight: 44.05 g/molcalculated · reference compound database; Average mass of one molecule, from reference compound database.
Exact mass: 44.026214747 Dacalculated · reference compound database; Mass of the most common isotopic form.
XLogP3: -0.3calculated · reference compound database; Estimated oil/water partition, computed by reference compound database.
Polar surface area: 17.1 Å²calculated · reference compound database; Polar surface area as computed by reference compound database.
Complexity: 10calculated · reference compound database; A rough measure of how intricate the structure is.
H-bond donors: 0calculated · reference compound database
H-bond acceptors: 1calculated · reference compound database
logP: 0.2052calculated · chemistry engine; Estimated preference for oil over water. Higher means more oil-like.
Topological polar surface area: 17.07 Å²calculated · chemistry engine; Surface area from polar atoms; relates to how easily a molecule crosses membranes.
H-bond donors: 0calculated · chemistry engine; Atoms that can donate a hydrogen bond.
H-bond acceptors: 1calculated · chemistry engine; Atoms that can accept a hydrogen bond.
Rotatable bonds: 0calculated · chemistry engine; Single bonds the molecule can freely twist around.
Molar refractivity: 11.738 cm³/molcalculated · chemistry engine; Relates to the molecule's polarisability.
Fraction sp³ carbons: 0.5calculated · chemistry engine; Share of carbon atoms with tetrahedral bonding.
QED drug-likeness: 0.355calculated · chemistry engine; Quantitative estimate of drug-likeness (0–1).

What it is made of

Elements

C Carbon2 atoms · 54.5% by mass
O Oxygen1 atom · 36.3% by mass
H Hydrogen4 atoms · 9.2% by mass

Percentages are of the molecular weight above, worked out the same way the molar mass calculator does it.

Structure

Heavy atoms, hydrogen excluded: 3
Total atoms, hydrogen included: 7
Rings: 0
Aromatic rings: 0
Stereocentres: 0
Formal charge: 0

Functional groups

Aldehyde
A carbonyl at the end of a chain, bonded to hydrogen.

Matched by structural pattern, not by a measurement.

The molecule in three dimensions

Rotate and inspect the atoms. Loaded only when you ask, so the page stays light.

The drawing above is a diagram of what is bonded to what. A molecule is not flat, and the model here is one low-energy shape generated from the connectivity — useful for seeing which groups can reach each other, and not a measured structure. A real sample is a population of conformations, interconverting.

Reactions it appears in

1 documented reaction involves Acetaldehyde, each with a written procedure and a source, and all of them are oxidation. A few are shown.

Oxidation of ethanol to acetaldehyde

Oxidation · as a product

A recorded experiment with its conditions, its yield where one was published, and a link to the source.

All 1 oxidation records

Other names for it

The systematic name on this record is acetaldehyde.

The sources also call it ethanal, acetic aldehyde, ethyl aldehyde, Acetylaldehyde, Acetaldehyd, Aldeide acetica, Acetic ethanol, Octowy aldehyd, Aldehyde acetique, RCRA waste number U001.

Structurally related

Nothing structurally close to Acetaldehyde has a page here yet.

Seen alongside it in reaction records

Molecules that appear in the same recorded reactions as Acetaldehyde. This says nothing about structure: most of them are the bases, solvents, ligands and catalysts the chemistry needed, and they are here because somebody put them in the same flask.

1,1-Dichloroethane

used as a reactant

C₂H₄Cl₂, 98.96 g/mol.

Where these values came from

reference compound database177
compound record
chemistry engine
structure perception

compound record.

What this page does not claim

Identifiers are copied from the source record, measured values are reported as published, and calculated values are marked as calculated. Nothing here is a hazard, purity or handling assessment — how the library is checked.