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

Chloroacetyl chloride

Chloroacetyl chloride is a liquid with a sharp, pungent, irritating odor.

CAS 79-04-9 C2H2Cl2O 112.94 g/mol Danger

01 · Identification

What Chloroacetyl chloride is

Chloroacetyl chloride is a liquid with a sharp, pungent, irritating odor. Its molecular formula is C2H2Cl2O and its molecular weight is 112.94 g/mol. It boils at 106 °C, melts at -21.7 °C.

Under the GHS it carries the signal word Danger. It is classed as corrosives.

CAS number79-04-9
EC number201-171-6
Index number607-080-00-1
Molecular formulaC2H2Cl2O
Molecular weight112.94 g/mol
Chemical class Corrosives

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 Chloroacetyl chloride
CodeHazard statement
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H372 Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H314 Causes severe skin burns and eye damage.
H400 Very toxic to aquatic life.

Supplemental EU statements: EUH014, EUH029

Precautionary statements: P260, P270, P271, P273, P280, P301, P302, P304, P310, P314, P330, P331, P352, P391, P501

03 · Physical and chemical properties

Chloroacetyl chloride 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 106 °C (222.8 °F) HSDB
106.11 °C (223 °F) NIOSH
105 °C (221 °F) at 760 mmHg CAMEO
Melting point -21.7 °C (-7.1 °F) HSDB
-21.67 °C (-7 °F) NIOSH
-22.5 °C (-8.5 °F) CAMEO
Density 1.42 g/cm³ NIOSH
1.4202 g/cm³ at 20 °C HSDB
Solubility Decomposed by water decomposes HSDB
Decomposes decomposes NIOSH
Decomposes (NIOSH, 2024) decomposes CAMEO
Vapor pressure 19 mmHg NIOSH
25.2 mmHg at 25 °C HSDB
Flash point 100 °C (212 °F) HSDB
Lower explosive limit (LEL) Noncombustible Liquid NIOSH
Vapor density 3.9 (air = 1) ICSC
Odor threshold An industrial hygienist was not able to detect odor at 0.011 ppm, found 0.023 ppm barely detectable, and 0.140 ppm "strong". HSDB
Critical temperature and pressure 307.85 °C (586.1 °F) HSDB
Corrosivity ... metals (corrosive) HSDB

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

04 · Handling and storage

Storing and handling Chloroacetyl chloride

Storage conditions

Store under nitrogen. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Keep away from water. Never allow product to get in contact with water during storage. Hydrolyzes readily.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong oxidizing agents, strong bases, alcohols, water.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

CHLOROACETYL CHLORIDE reacts rapidly with water. Incompatible with strong oxidizing agents, alcohols, bases (including amines). May react vigorously or explosively if mixed with diisopropyl ether or other ethers in the presence of trace amounts of metal salts [J. Haz. Mat., 1981, 4, 291].

Source: CAMEO Chemicals

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

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