Chloromethane

Chloromethane

Names
IUPAC name Chloromethane
Other names Refrigerant-40 R-40 Methyl chloride Monochloromethane
Identifiers
CAS Number	74-87-3 Y
3D model (Jmol)	Interactive image
Beilstein Reference	1696839
ChEBI	CHEBI:36014 Y
ChEMBL	ChEMBL117545 Y
ChemSpider	6087 Y
ECHA InfoCard	100.000.744
EC Number	200-817-4
Gmelin Reference	24898
KEGG	C19446 N
MeSH	Methyl+Chloride
PubChem	6327
RTECS number	PA6300000
UNII	A6R43525YO Y
UN number	1063
InChI InChI=1S/CH3Cl/c1-2/h1H3 Y Key: NEHMKBQYUWJMIP-UHFFFAOYSA-N Y
SMILES CCl
Properties
Chemical formula	CH3Cl
Molar mass	50.49 g·mol−1
Appearance	Colorless gas
Odor	Faint, sweet odor
Density	1.003 g/mL (-23.8 °C, liquid)2.3065 g/L (0 °C, gas)
Melting point	−97.4 °C (−143.3 °F; 175.8 K)
Boiling point	−23.8 °C (−10.8 °F; 249.3 K)
Solubility in water	5.325 g L−1
log P	1.113
Vapor pressure	506.09 kPa (at 20 °C (68 °F))
Henry's law constant (kH)	940 nmol Pa−1 kg−1
Magnetic susceptibility (χ)	-32.0·10−6 cm3/mol
Structure
Coordination geometry	Tetragonal
Molecular shape	Tetrahedron
Thermochemistry
Std molar entropy (So298)	234.36 J K−1 mol−1
Std enthalpy of formation (ΔfHo298)	−83.68 kJ mol−1
Std enthalpy of combustion (ΔcHo298)	−764.5–−763.5 kJ mol−1
Hazards
Main hazards	carcinogen
Safety data sheet	See: data page
GHS pictograms
GHS signal word	DANGER
GHS hazard statements	H220, H351, H373
GHS precautionary statements	P210, P281, P410+403
EU classification (DSD)	F+ Xn T
R-phrases	R12, R40, R48/20
S-phrases	(S2), S16, S33
NFPA 704	4 2 0
Flash point	−20 °C (−4 °F; 253 K)
Autoignition temperature	625 °C (1,157 °F; 898 K)
Explosive limits	8.1%-17.4%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	1800 mg/kg (oral, rat) 5.3 mg/L/4 h (inhalation, rat)
LC50 (median concentration)	72,000 ppm (rat, 30 min) 2200 ppm (mouse, 6 hr) 2760 ppm (mammal, 4 hr) 2524 ppm (rat, 4 hr)
LCLo (lowest published)	20,000 ppm (guinea pig, 2 hr) 14,661 ppm (dog, 6 hr)
US health exposure limits (NIOSH):
PEL (Permissible)	TWA 100 ppm C 200 ppm 300 ppm (5-minute maximum peak in any 3 hours)
REL (Recommended)	Ca
IDLH (Immediate danger)	Ca [2000 ppm]
Related compounds
Related alkanes	Chloroiodomethane Bromochloromethane Dibromochloromethane
Related compounds	2-Chloroethanol
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Chloromethane, also called methyl chloride, Refrigerant-40, R-40 or HCC 40, is a chemical compound of the group of organic compounds called haloalkanes. It was once widely used as a refrigerant. It is a colorless extremely flammable gas with a mildly sweet odor. Due to concerns about its toxicity, it is no longer present in consumer products. Chloromethane was first synthesized by the French chemists Jean-Baptiste Dumas and Eugene Peligot in 1835 by boiling a mixture of methanol, sulfuric acid, and sodium chloride. This method is similar to that used today.

Chloromethane is the most abundant organohalogen, anthropogenic or natural, in the atmosphere.

Laboratory cultures of marine phytoplankton (Phaeodactylum tricornutum, Phaeocystis sp., Thalassiosira weissflogii, Chaetoceros calcitrans, Isochrysis sp., Porphyridium sp., Synechococcus sp., Tetraselmis sp., Prorocentrum sp., and Emiliana huxleyi) produce CH₃Cl, but in relatively insignificant amounts. An extensive study of 30 species of polar macroalgae revealed the release of significant amounts of CH₃Cl in only Gigartina skottsbergii and Gymnogongrus antarcticus.

The salt marsh plant Batis maritima contains the enzyme methyl chloride transferase that catalyzes the synthesis of CH₃Cl from S-adenosine-L-methionine and chloride. This protein has been purified and expressed in E. coli, and seems to be present in other organisms such as white rot fungi (Phellinus pomaceus), red algae (Endocladia muricata), and the ice plant (Mesembryanthemum crystallinum), each of which is a known CH₃Cl producer.