Monohalomethane (original) (raw)
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| Structural formula |  |
 |
 |
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|---|---|---|---|---|
| Name | FluoromethaneMethyl fluoride | ChloromethaneMethyl chloride | BromomethaneMethyl bromide | IodomethaneMethyl iodide |
| Melting point | −137,8 °C[1] | −97,4 °C[2] | −93,7 °C[3] | −66 °C[4] |
| Boiling point | −78,4 °C[1] | −23,8 °C[2] | 4,0 °C[3] | 42 °C[4] |
| Space-filling model |  |
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The monohalomethanes are organic compounds in which a hydrogen atom in methane is replaced by a halogen. They belong to the haloalkanes or to the subgroup of halomethanes.
The four common[a] members are fluoromethane, chloromethane, bromomethane and iodomethane.
Historical name for this group is methyl halides; it's still widely used. The compounds of this class are often described as CH3X or MeX (X - any halogen, Me - methyl group).
There are analogs with more than one hydrogen atom in methane is replaced by a halogen:
- Dihalomethane, CH2X2, two hydrogen atoms replaced
- Trihalomethane, CHX3, three hydrogen atoms replaced
- Tetrahalomethane, CX4, all four hydrogen atoms replaced
Analogs with carbon atom replaced with a heavier group 14 element are also known:
- Monohalosilane, SiH3X (with silicon, related to silane)
- Monohalogermane, GeH3X (with germanium, related to germane)
- Monohalostannane, SnH3X (with tin, related to stannane)
- Methyl halide transferase, an enzyme producing some methyl halides
^ Highly radioactive CH3At (methyl astatide) has been detected.[5] The known isotopes of even heavier group 17 element, tennessine, are too short-lived to allow for chemical experimentation.
^ a b Record of Fluoromethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health, accessed on 2020-02-29.
^ a b Record of Chloromethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health, accessed on 2020-02-29.
^ a b Record of Bromomethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health, accessed on 2020-02-29.
^ a b Record of Iodomethane in the GESTIS Substance Database of the Institute for Occupational Safety and Health, accessed on 2020-02-29.
^ "Chemical Fact Sheet: Astatine". European Virtual Institute for Speciation Analysis (EVISA).