Sodium chlorate, toxicity

This is the reaction by which sodium chlorate is manufactured commercially. In the present context, however, the formation of chlorates is generally undesirable since they tend to be explosive and toxic. The reaction given by Equation 26.2 is strongly affected by pH and temperature as well as the hypochlorite ion concentration. As the alkali becomes exhausted, and the system is thus over-chlorinated, the rate of chlorate formation is greatly accelerated as the reaction becomes auto-catalysed by hypo-chlorous acid. The acid is formed by... 

From the mechanism shown in Scheme 7.23, we would expect the dihydroxylation with syn-selectivity. The cyclic intermediate may be isolated in the osmium reaction, which is formed by the cycloaddition of OSO4 to the alkene. Since osmium tetroxide is highly toxic and very expensive, the reaction is performed using a catalytic amount of osmium tetroxide and an oxidizing agent such as TBHP, sodium chlorate, potassium ferricyanide or NMO, which regenerates osmium tetroxide. For example, Upjohn dihydroxylation allows the syn-selective preparation of 1,2-diols from alkenes by the use of catalytic amount of OSO4 and a stoichiometric amount of an oxidant such as NMO. 

An oxidant. Combusdble when exposed to heat and flame. Moderate explosion hazard when exposed to heat or flame. Explosive reacdon with solid or concentrated alkali + heat (e.g., sodium hydroxide or potassium hydroxide), aluminum chloride + phenol (at 120°C), aniline + glycerol + sulfuric acid, nitric + sulfuric acid + heat. Forms explosive mixmres with aluminum chloride, oxidants (e.g., fluorodinitromethane, uranium perchlorate, tetranitromethane, sodium chlorate, nitric acid, nitric acid + water, peroxodisulfuric acid, dinitrogen tetraoxide), phosphorus pentachloride, potassium, sulfuric acid. Reacts violendy with aniline + glycerin, N2O, AgC104. To fight fire, use water, foam, CO2, dry chemical. Incompadble with potassium hydroxide. When heated to decomposidon it emits toxic flames of NOx. See also NITRO COMPOUNDS OF AROMATIC HYDROCARBONS. 

ARSENOLITE or ARSENOUS ACID or ARSENOUS ACID ANHYDRIDE or ARSENOUS ANHYDRIDE (1327-53-3) AS2O3 Noncombustible solid. Reacts, possibly violently, with acids, aluminum, aluminum chloride, chlorine trifluoride, chromic oxide, fluorine, fluorides, halogens, hydrogen fluoride, mercury, oxygen fluoride, phosphorus pentoxide, rubidium acetylide, sodium chlorate, sodium hydroxide, sulfiiric acid, tannic acid, zinc iron in solution. Contact with acids or acid mists releases toxic and flammable arsine gas. The aqueous... 

MERCURIC THIOCYANATE (592-85-8) Hg(SCN)i Moderately unstable solid. Possible violent reaction with strong oxidizers strong acids organic peroxides, peroxides and hydroperoxides potassium chlorate potassium iodate, silver nitrate, sodium chlorate, nitric acid. Incompatible with ammonia, chlorates, hydrozoic acid, methyl isocyanoacetate, nitrates, nitrites, perchlorates, sodium peroxyborate, trinitrobenzoic acid, urea nitrate. When heated, this material swells to many times its original bulk. Attacks aluminum in the presence of moisture. Decomposes above 329°F/165°C, releasing toxic mercury and cyanide fumes, and sulfur and nitrogen oxides. On small fires, use dry chemical powder (such as Purple-K-Powder), alcohol-resistant foam, or COj extinguishers. MERCURIC (Spanish) (7439-97-6) see mercury. 

METHYL SULFOCYANATE (556-64-9) CjHjNS May be flammable. Violent reactions have occurred when mixed with chlorates, nitrates, nitric acid, peroxides and hydroperoxides perchlorates, potassium chlorate, and sodium chlorate. Incompatible with acid fiimes and/or chlorosulfonic acid, oleum, sulfuric acid, and other mineral acids, releasing deadly toxic hydrogen cyanide gas, and toxic oxides of nitrogen and sulfur afad nitriles. On small fires, use dry chemical powder (such as Purple-K-Powder), water spray, or COj extinguishers. 

SODIUM RHODANIDE (540-72-7) NaSCN Exposure to light causes slow decomposition, forming cyanide, sulfur oxides, and nitrous vapors. Violent reaction, possibly explosion, with strong oxidizers, organic peroxides, nitric acid. Incompatible with acids, bases, chlorates, anunonia, amines, amides, alcohols, glycols, caprolactam, nitrates, peroxides and hydroperoxides, potassium chlorate, potassium iodate, silver nitrate, sodium chlorate. Contact with sulfuric acid forms toxic carbonyl sulfide gas. Forms explosive mixture with sodium nitrate. Thermal decomposition releases oxides of sulfur and nitrogen. 

Sodium Chlorate. Atlacide De-Fol-Ate. CINa-Oj mol Wt 106.45. Cl 33.31%, Na 21.60%, O 45.09%, NaQOj. The chlorate of commerce is about 99% pure. Produced from sodium chloride by electrolysis Faith, Keyes Clark s Industrial Chemicals, F, A. Lowenheim, M. K. Moran, Eds. (Wiley-Inrerscience, New York, 4th ed., 1975) pp 716-721. Toxicity Ulrich, J. Pharmacol Exp Ther. 35, 1 (1929). 

EXPLOSION and FIRE CONCERNS not flammable poisonous gases are produced in fire NFPA rating Health 3, Flammability 1, Reactivity 0 reacts with some silver compounds to form explosive silver oxalate reacts explosively with strong oxidizing materials violent reaction with furfuryl alcohol, silver, sodium chlorate, and NaOCl combustion may produce toxic gases, including formic acid use water spray, dry chemical, alcohol foam, or carbon dioxide for firefighting purposes. 

Herbicides are used to kill plants. Sodium chlorate, NaC103 and sodium arsenite, Na3As03, were commonly used as weed killers in the first half of the twentieth century, but inorganic arsenic compounds, in particular, are toxic to mammals. Organic herbicides are now used. They are much more toxic to certain types of plants than to others, so they can be used as selective weedkillers. Atrazine, which is a member of a class of herbicides called the triazines, is widely used to kill weeds in cornfields. The triazines contain six-membered rings with alternating carbon and nitrogen atoms. The effects of atrazine on human health are not yet clear. 

Bio/dynamics, Inc. (1987a) A subchronic (3-month) oral toxicity study In the dog via gavage administration with sodium chlorate. East Millstone, NJ, USA (Report No. 86-3114 for Sodium Chlorate Task Force, Oklahoma City, OK, USA) [cited In World Health Organization, 2003]. 

Household chlorine bleach is a dilute solution of sodium chlorate(i) (sodium hypochlorite). It is prepared by absorbing chlorine gas into cold sodium hydroxide solution. More concentrated solutions are used to disinfect drinking water and swimming pools. Bleach should never be mixed with other household cleaners. With bleach, acid-based cleaners produce chlorine and ammonia-based products produce toxic chloramines, for example NH2CI. 

Some dehydration reactions of sulfuric acid can be very vigorous. For example, the reaction with perchloric acid produces unstable CI2O7, and a violent explosion can result. Concentrated sulfuric acid produces dangerous or toxic products with a number of other substances such as toxic carbon monoxide (CO) from reaction with oxalic acid, H2C2O4 toxic bromine and sulfur dioxide (Bf2 and SO2) from reaction with sodium bromide, NaBr and toxic, unstable chlorine dioxide (CIO2) from reaction with sodium chlorate, NaClOj. 

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