Substance profile
Bromomethane
Bromomethane is colorless, transparent, easily liquified gas or volatile liquid and is odorless.
01 · Identification
What Bromomethane is
Bromomethane is colorless, transparent, easily liquified gas or volatile liquid and is odorless. Its molecular formula is CH3Br and its molecular weight is 94.94 g/mol. It boils at 3.4 °C, melts at -93.7 °C.
Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).
Other names for Bromomethane
- methylbromide
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 |
|---|---|
| H341 | Suspected of causing genetic defects <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. |
| H335 | May cause respiratory irritation. |
| 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>. |
| H315 | Causes skin irritation. |
| H319 | Causes serious eye irritation. |
| H400 | Very toxic to aquatic life. |
| H420 | Harms public health and the environment by destroying ozone in the upper atmosphere |
Precautionary statements: P201, P260, P264, P270, P271, P273, P280, P301, P302, P304, P305, P308, P310, P313, P314, P330, P332, P337, P338, P352, P391, P501
03 · Physical and chemical properties
Bromomethane 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 | 3.4 °C (38.1 °F) | HSDB | |
| 3.33 °C (38 °F) | NIOSH | ||
| 3.56 °C (38.4 °F) | at 760 mmHg | CAMEO | |
| Melting point | -93.7 °C (-136.7 °F) | HSDB | |
| -93.89 °C (-137 °F) | NIOSH | ||
| -93.33 °C (-136 °F) | CAMEO | ||
| Density | 1.6755 g/cm³ | at 20 °C | HSDB |
| 0.004 g/cm³ | at 0 °C | HSDB | |
| Solubility | In water, 18.5 g/L at 20 °C | at 20 °C | HSDB |
| In water, 15,200 mg/L at 25 °C | at 25 °C | HSDB | |
| In water, 13.4 g/L at 25 °C | at 25 °C | HSDB | |
| Vapor pressure | 1444 mmHg | NIOSH | |
| 14200 mmHg | at 20 °C | HSDB | |
| 1620 mmHg | at 25 °C | HSDB | |
| Flash point | 194 °C (381.2 °F) | Open cup vs closed cup not specified | HSDB |
| 194 °C (381.2 °F) | ICSC | ||
| NA (Gas) | NIOSH | ||
| Autoignition temperature | 537 °C (998.6 °F) | HSDB | |
| 537.22 °C (999 °F) | CAMEO | ||
| Lower explosive limit (LEL) | 10 % by volume | HSDB | |
| 13.5 % by volume | HSDB | ||
| Upper explosive limit (UEL) | 16 % by volume | HSDB | |
| 14.5 % by volume | HSDB | ||
| Vapor density | 3.27 (air = 1) | CAMEO | |
| 3.3 (air = 1) | ICSC | ||
| 3.27 (air = 1) | at 20 °C | HSDB | |
| Odor threshold | In mg/cu m: odor low 80; odor high 4,000 | HSDB | |
| Low threshold= 80 mg/cu m, High threshold= 4000 mg/cu m | HSDB | ||
| Odor Threshold Low: 20.0 [ppm] | Haz-Map | ||
| Critical temperature and pressure | 194 °C (381.2 °F) | HSDB | |
| Corrosivity | Corrosive to aluminum, magnesium & their alloys | HSDB | |
| In presence of moisture, corrosive to tin, zinc, & other alloys. | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Source notes
Further notes on Bromomethane
These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.
Corrosivity
When dry (<100 ppm water), methyl bromide is inert toward most materials of construction. Aluminum, magnesium, zinc, and alloys of these metals should not be used because under some conditions, dangerous pyrophoric Grignard-type compounds may be formed. ... Nylon and polyvinyl chloride should be avoided for handling methyl bromide.
Source: HSDB
05 · Handling and storage
Storing and handling Bromomethane
Storage conditions
Poison gas. Color Code-Blue: Health Hazard/ Poison: Store in a secure poison location. Prior to working with this chemical you should be trained on its proper handling and storage. Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Store in well-ventilated area away from direct sunlight. Maintain temperature below 40 °C; avoid heat sources. Protect against physical damage. A regulated, marked area should be established where this chemical is handled, used, or stored in compliance with OSHA Standard 1910.1045.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Incompatible materials: Strong oxidizing agents, Plastics, Rubber, Aluminum, Strong bases, and its alloys, Alkali metals, Zinc.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
METHYL BROMIDE is incompatible with metals, dimethyl sulfoxide, ethylene oxide. [Lewis]. Can give flammable products if mixed with potassium hydroxide, sodium hydroxide and other strong bases. Methyl bromide in a steel tank reacted with an aluminum tube (part of the level gauge) producing methyl aluminum bromide. When the latter was subsequently exposed to air, enough heat was produced to ignite the methyl bromide-compressed air mixture above the liquid layer. The ensuing explosion shattered the tank (also incompatible with zinc, magnesium, and alloys)[Chem. Eng. Pro. 58(8). 1962]. A reaction between methyl bromide and dimethyl sulfoxide resulted in an explosion that shattered the apparatus [NFPA 491M. 1991].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Bromomethane in the storage compatibility matrix →