Substance profile
Chloromethane
Chloromethane is a colorless compressed gas or liquid with a faint sweet ethereal odor.
01 · Identification
What Chloromethane is
Chloromethane is a colorless compressed gas or liquid with a faint sweet ethereal odor. Its molecular formula is CH3Cl and its molecular weight is 50.49 g/mol. It boils at -23.7 °C, melts at -97.6 °C.
Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).
Other names for Chloromethane
- methyl chloride
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.
| Code | Hazard statement |
|---|---|
| H220 | Extremely flammable gas. |
| H351 | Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H373 | May cause 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>. |
Precautionary statements: P201, P210, P233, P260, P270, P280, P308, P313, P314, P403
03 · Physical and chemical properties
Chloromethane 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 | -23.7 °C (-10.7 °F) | HSDB | |
| -24.44 °C (-12 °F) | NIOSH | ||
| -24.22 °C (-11.6 °F) | at 760 mmHg | CAMEO | |
| Melting point | -97.6 °C (-143.7 °F) | HSDB | |
| -97.78 °C (-144 °F) | NIOSH | ||
| -97.22 °C (-143 °F) | CAMEO | ||
| Density | 0.91 g/cm³ | ICSC | |
| 0.9203 g/cm³ | at 20 °C | HSDB | |
| 0.911 g/cm³ | at 25 °C, at 760 mmHg | HSDB | |
| Solubility | Soluble in ethanol; miscible with ethyl ether, acetone, benzene and chloroform | HSDB | |
| Solubility at 20 °C (mL/100 mL): benzene 4723, carbon tetrachloride 3756, glacial acetic acid 3679, ethanol 3740; miscible with chloroform, ether | at 20 °C | HSDB | |
| In water, 5040 mg/L at 25 °C | at 25 °C | HSDB | |
| Vapor pressure | 3800 mmHg | NIOSH | |
| 4300 mmHg | at 25 °C | HSDB | |
| 4298 mmHg | at 25 °C | ICSC | |
| Flash point | -45.56 °C (-50 °F) | HSDB | |
| -45.5 °C (-49.9 °F) | CAMEO | ||
| -45 °C (-49 °F) | OSHA | ||
| Autoignition temperature | 632.22 °C (1170 °F) | HSDB | |
| 632 °C (1169.6 °F) | ICSC | ||
| Lower explosive limit (LEL) | 8.1 % by volume | HSDB | |
| Upper explosive limit (UEL) | 17.4 % by volume | HSDB | |
| 17 % by volume | HSDB | ||
| Vapor density | 1.8 (air = 1) | HSDB | |
| 2.47 (air = 1) | ICSC | ||
| Odor threshold | Odor recognition in air: 1.00x10+1 ppm (chemically pure) | HSDB | |
| Odor ... not noticeable at dangerous concentrations. | HSDB | ||
| Odor Threshold (air) 21 mg/cu m | HSDB | ||
| Critical temperature and pressure | 143.1 °C (289.6 °F) | HSDB | |
| Corrosivity | Methyl chloride will attack some forms of plastics, rubber and coatings. | HSDB | |
| Attacks aluminum, magnesium, and zinc. | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Chloromethane
Storage conditions
Keep container tightly closed in a dry and well-ventilated place. Contents under pressure. Moisture sensitive. Storage class (TRGS 510): Gases
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Incompatible materials: Strong oxidizing agents, Iron
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
METHYL CHLORIDE can react vigorously with oxidizing agents. May react explosively with sodium, potassium, sodium-potassium alloy, magnesium, zinc. Reacts with aluminum powder in the presence of catalytic amounts of aluminum chloride to form pyrophoric trimethylaluminum. When heated to decomposition, it emits highly toxic fumes of chlorine [Bretherick, 5th ed., 1995, p. 176].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Chloromethane in the storage compatibility matrix →