74-97-5 Usage
Chemical Properties
Different sources of media describe the Chemical Properties of 74-97-5 differently. You can refer to the following data:
1. white to light yellow crystal powder
2. Chlorobromomethane is a clear, colorless, to
pale-yellow liquid with a chloroform-like odor
Physical properties
Clear, colorless liquid with a sweet, chloroform-like odor
Uses
Different sources of media describe the Uses of 74-97-5 differently. You can refer to the following data:
1. Fire fighting agent
2. Bromochloromethane is used primarily as an extinguishing agent due to its oxygen-depleting properties.
Definition
ChEBI: A one-carbon compound substituted by a chloro and a bromo group.
General Description
A clear colorless liquid with a sweet chloroform-like odor. Denser than water (density 1.991 g / cm3) and insoluble in water. Hence sinks in water. Boiling point 68°C. Vapors may cause illness if inhaled. Nonflammable. When exposed to high temperatures may emit toxic fumes. Used as a fire extinguishing agent.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Bromochloromethane is sensitive to light (may discolor). Incompatible with strong bases and strong oxidizing agents. Also incompatible with active metals, calcium, aluminum, magnesium, zinc and their alloys. Attacks some forms of plastics, rubber and coatings. .
Hazard
By inhalation.
Health Hazard
Toxic by ingestion. Vapors may cause dizziness or suffocation. Exposure in an enclosed area may be very harmful. Contact may irritate or burn skin and eyes. Fire may produce irritating and/or toxic gases. Runoff from fire control or dilution water may cause pollution.
Fire Hazard
Some of these materials may burn, but none ignite readily. Most vapors are heavier than air. Air/vapor mixtures may explode when ignited. Container may explode in heat of fire.
Safety Profile
Mildly toxic by
ingestion and inhalation. Mutation data
reported. This material has a narcotic action
of moderate intensity, although of
prolonged duration. Animals exposed for
several weeks to 1000 pprn had blood
bromide levels as high as 350 mgl100 g.
Therefore, until further data are available, it
should be considered at least as toxic as carbon tetrachloride and more than minimal
exposure to its vapors should be avoided.
Dangerous; when heated to decomposition
it emits highly toxic fumes of Brand Cl-.
See also BROMIDES and
CHLORINATED HYDROCARBONS,
ALIPHATIC.
Potential Exposure
This compound is used in brominated
flame retardants; a fire-extinguishing agent; and in organic
synthesis
Carcinogenicity
The U.S. EPA classification is D
(not classifiable as to human carcinogenicity). Bromochloromethane
is structurally similar to dichloromethane (methylene
chloride), which is classified B2 (probable human
carcinogen). The classification is based on the lack of data
regarding the carcinogenicity of bromochloromethane in
humans or animals; however, there are data indicative of
genotoxic effects and structural relationships to halogenated
methanes classified as B2 (probable human carcinogens).
Source
No MCLGs or MCLs have been proposed, however, a DWEL of 0.5
mg/L was recommended (U.S. EPA, 2000).
Naturally formed by algal biological processes (Orkin et al., 1997) and is a disinfection
byproduct in public water treatment systems.
Environmental fate
Biological. When bromochloromethane (5 and 10 mg/L) was statically incubated in the dark at
25 °C with yeast extract and settled domestic wastewater inoculum for 7 d, 100% biodegradation
with rapid adaptation was observed (Tabak et al., 1981).
Photolytic. The following rate constants were reported for the reaction of bromochloromethane
and OH radicals as measured by both flash photolysis resonance fluorescence and discharge flow
electron paramagnetic resonance techniques (x 10-13 cm3/molecule?sec): 0.91 at 4 °C, 1.11–1.13 at
25 °C, 1.32–1.34 at 40 °C, 1.55–1.58 at 57 °C, 1.76–1.90 at 76 °C, 2.10–2.26 at 97 °C (Orkin et
al., 1997).
Chemical/Physical. Although no products were identified, the estimated hydrolysis half-life in
water at 25 °C and pH 7 is 44 yr (Mabey and Mill, 1978). Bromochloromethane reacts with
bisulfide ion (HS-), produced by microbial reduction of sulfate, forming 1,3,5-trithiane and
dithiomethane. Estimated reaction rate constants at 25 and 35 °C were 7.29 x 10-5 and 2.42 x 10-
4/M?sec, respectively (Roberts et al., 1992).
Shipping
UN1887 Bromochloromethane, Hazard Class:
6.1; Labels: 6.1-Poisonous materials.
Incompatibilities
Incompatible with strong oxidizers (possible explosion), reducing agents, bases, carbonates, furyl alcohol, chemically active metals, such as calcium; base metals
in the presence of moisture, powdered aluminum; zinc, magnesium. Liquid attacks some plastics, rubber, and coatings.
Waste Disposal
Incinerate together with flammable solvent in furnace equipped with afterburner and
alkali scrubber.
Check Digit Verification of cas no
The CAS Registry Mumber 74-97-5 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 7 and 4 respectively; the second part has 2 digits, 9 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 74-97:
(4*7)+(3*4)+(2*9)+(1*7)=65
65 % 10 = 5
So 74-97-5 is a valid CAS Registry Number.
InChI:InChI=1/CH2BrCl/c2-1-3/h1H2
74-97-5Relevant articles and documents
Mixed tetrahaloborate ions. Detection and study by nuclear magnetic resonance
Hartman,Schrobilgen
, p. 940 - 951 (1972)
BF4-, BCl4-, BBr4-, and BI4- undergo halogen exchange in methylene chloride solution to form the mixed tetrahaloborate ions, for which 19F and 11B nmr data are presented. A previous report of very rapid halogen exchange in the BF4--BCl4- system is incorrect. Only in the BF4--BI4- system is halogen redistribution so rapid that separate nmr signals are not observed for the mixed-halogen anions. Exchange with methylene halide solvents gives rise to ternary-halogen species such as BF2ClBr-. Additional methods of preparation of mixed tetrahaloborate anions are investigated. The nmr parameters of the mixed tetrahaloborate anions show trends which resemble those of the mixed boron trihalides. The trends can be interpreted in terms of the presence of boron-fluorine π bonding. The results of CNDO/2 calculations provide an alternative interpretation of the trends in chemical shifts. The 11B and F19 chemical shifts of the tetrahaloborate anions are found to fit Malinowski's criteria of pairwise additivity. .
Facile continuous process for gas phase halogen exchange over supported alkyl phosphonium salts
Sharma, Priti,Sasson, Yoel
, p. 2824 - 2828 (2018/02/06)
Chloride-bromide halogen exchange was realized when a mixture of an alkyl chloride and an alkyl bromide were reacted over a supported molten alkyl phosphonium catalyst. Conversion was found to be near equilibrium in a tubular flow reactor at 150 °C and 1500 GHSV. The catalyst was prepared by impregnation of alumina or silica support and found to be highly stable for relatively long periods of time. A pathway for the catalytic cycle is proposed.
Kinetics of the Reactions of Halogenated Methyl Radicals with Molecular Bromine
Timonen, R. S.,Seetula, J. A.,Niiranen, J.,Gutman, D.
, p. 4009 - 4014 (2007/10/02)
The kinetics of seven reactions of halogenated methyl radicals (CH2Cl, CHCl2, CFCl2, CF2Cl, CF3, CH2Br, and CH2I) with molecular bromine were studied by using a heatable tubular reactor coupled to a photoionization mass spectrometer.Rate constants were measured as a function of temperature, typically between 296 and 532 K.Arrhenius activation energies were found to be small negative values (typically -2 kJ mol-1) for all reactions studied with the exception of that of the CF3 + Br2 reaction (whose activation energy is positive, but which could not determined accurately).The pattern of reactivity among 11 reactions of substituted methyl radicals with Br2 (which includes the 7 reactions studied here and 4 C(H)x(CH3)3-x + Br2 reactions (x = 0-3) studied earlier) has been accounted for by the inductive effect of the substituent atoms or groups.The sum of the Pauling electronegativities of these substituents provides a useful measure of their total inductive effect on the reaction rate constant.
