Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

Build a label

Substance profile

2-furaldehyde

2-furaldehyde is colorless, oily liquid Turns yellow to brown on exposure to air and light and resinifies with a peculiar odor, somewhat resembling the odor of benzaldehyde.

CAS 98-01-1 C5H4O2 96.08 g/mol Danger

01 · Identification

What 2-furaldehyde is

2-furaldehyde is colorless, oily liquid Turns yellow to brown on exposure to air and light and resinifies with a peculiar odor, somewhat resembling the odor of benzaldehyde. Its molecular formula is C5H4O2 and its molecular weight is 96.08 g/mol. It boils at 162 °C, melts at -38.1 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 2nd degree.

CAS number98-01-1
EC number202-627-7
Index number605-010-00-4
Molecular formulaC5H4O2
Molecular weight96.08 g/mol
Chemical class Flammable agents - 2nd degree

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to 2-furaldehyde
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H331 Toxic if inhaled.
H301 Toxic if swallowed.
H312 Harmful in contact with skin.
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H319 Causes serious eye irritation.

Precautionary statements: P201, P260, P264, P270, P271, P280, P301, P302, P304, P305, P308, P310, P312, P313, P330, P332, P337, P338, P352

03 · Physical and chemical properties

2-furaldehyde properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 161.7 °C (323.1 °F) HSDB
161.67 °C (323 °F) NIOSH
161.72 °C (323.1 °F) at 760 mmHg CAMEO
Melting point -38.1 °C (-36.6 °F) HSDB
-36.67 °C (-34 °F) NIOSH
-36.5 °C (-33.7 °F) CAMEO
Density 1.16 g/cm³ NIOSH
1.1594 g/cm³ at 20 °C HSDB
1.159 g/cm³ at 20 °C CAMEO
Solubility Soluble in benzene, chloroform; very soluble in ethanol, acetone; miscible with ethyl ether HSDB
Soluble in alcohol, ether; 8.3% soluble in water at 20 °C at 20 °C HSDB
In water, 7.41X10+4 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 2 mmHg NIOSH
1 mmHg at 20 °C CAMEO
1.1251 mmHg at 20 °C ICSC
Flash point 60 °C (140 °F) HSDB
Autoignition temperature 316 °C (600.8 °F) HSDB
392.78 °C (739 °F) CAMEO
315 °C (599 °F) ICSC
Lower explosive limit (LEL) 2.1 % by volume HSDB
Upper explosive limit (UEL) 19.3 % by volume HSDB
Vapor density 3.3 (air = 1) HSDB
3.31 (air = 1) CAMEO
Odor threshold Detection in water: 3.00X10+3 ppb (gas chromatically pure) HSDB
0.0240 mg/cu m (odor low) 20.0 mg/cu m (odor high) HSDB
Recognition/human odor perception: 1.0 mg/cu m HSDB
Critical temperature and pressure 396.85 °C (746.3 °F) HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling 2-furaldehyde

Storage conditions

Keep in air tight container and protect from light

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

...Can react with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

FURFURAL reacts with sodium hydrogen carbonate. It also can react with strong oxidizers. An exothermic resinification of almost explosive violence can occur upon contact with strong mineral acids or alkalis. It forms condensation products with many types of compounds, including phenol, amines and urea. (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 2-furaldehyde in the storage compatibility matrix →

Get the free GHS / CLP / OSHA deadline calendar

Verified 2026–2029 compliance dates in one PDF — plus alerts when the rules change.