Provenance

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

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Substance profile

Chloroacetaldehyde

Chloroacetaldehyde is a colorless liquid with an acrid, penetrating odor.

CAS 107-20-0 C2H3ClO 78.5 g/mol Danger

01 · Identification

What Chloroacetaldehyde is

Chloroacetaldehyde is a colorless liquid with an acrid, penetrating odor. Its molecular formula is C2H3ClO and its molecular weight is 78.5 g/mol. It boils at 85.5 °C, melts at -16.3 °C, is miscible with water.

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

CAS number107-20-0
EC number203-472-8
Index number605-025-00-6
Molecular formulaC2H3ClO
Molecular weight78.5 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 Chloroacetaldehyde
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>.
H330 Fatal if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H314 Causes severe skin burns and eye damage.
H400 Very toxic to aquatic life.

Precautionary statements: P201, P260, P270, P271, P273, P280, P301, P302, P304, P308, P310, P313, P330, P331, P352, P391, P501

03 · Physical and chemical properties

Chloroacetaldehyde 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 85.5 °C (185.9 °F) HSDB
85.56 °C (186 °F) NIOSH
85 °C (185 °F) at 760 mmHg CAMEO
Melting point -16.3 °C (2.7 °F) HSDB
-19.44 °C (-3 °F) NIOSH
-16.11 °C (3 °F) CAMEO
Density 1.19 g/cm³ NIOSH
1.19 g/cm³ at 25 °C HSDB
Solubility Miscible in all proportions with water HSDB
Soluble in ether HSDB
Soluble in acetone and methanol HSDB
Vapor pressure 100 mmHg NIOSH
99.7582 mmHg at 20 °C ICSC
Flash point 87.78 °C (190 °F) HSDB
Autoignition temperature 88 °C (190.4 °F) HSDB
Lower explosive limit (LEL) Above 88 °C explosive vapor/air mixtures may be formed. HSDB
Contact with oxidizing materials & acids may cause ... explosions. HSDB
Class IIIA Combustible Liquid: Fl.P. at or above 140 °F and below 200 °F. NIOSH
Vapor density 2.7 (air = 1) CAMEO
Odor threshold Odor threshold: 3.0 mg/cu m HSDB

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

04 · Handling and storage

Storing and handling Chloroacetaldehyde

Storage conditions

Safe Storage: Separated from strong oxidants, acids, metals and food and feedstuffs. /Chloroacetaldehyde (40% Solution)/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Oxidizers, acids.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

2-CHLOROETHANAL polymerizes on standing. At greater than 50% concentration in water, it forms an insoluble hemihydrate. Sensitive to heat. Reacts with oxidizing agents. Incompatible with acids and water (NTP, 1992). Burns to give poisonous and irritating gases.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Chloroacetaldehyde in the storage compatibility matrix →

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