Nitrous acid sulfur dioxide reaction with

CHEMICAL PROPERTIES reacts vigorously with oxidizing materials polymerization reaction on contact with strong acid, strong base, weak acid conditions (e.g., nitrous fumes, sulfur dioxide, carbon dioxide) may form shock sensitive peroxides or acids FP (-26°C, -15°F) LFL/UFL(2.8%, 31%) AT (235°C, 455°F) HC (-12,500 Btu/lb, -6,950 cal/g, -290 x 105J/kg). 

N-Nitrosamines are formed in foods by the reaction of secondary and tertiary amines with a nitrosating agent, usually nitrous anhydride, which forms from nitrite in acidic, aqueous solution. NDMA is the most common volatile amine found in food. Food constituents and the physical make-up of the food can affect the extent of nitrosamine formation. Ascorbic acid and sulfur dioxide have been used to inhibit the formation of nitrosamines. 

Hofmann s classical synthesis of 3,5-disubstituted 1,2,4-thiadiazoles by the oxidation of thioamides (1869)3 continues to be further exemplified. The oxidants employed include iodine,9-11 bromine,12 chlorine,13 and nitrous acid,14 as well as /V-chlorobenzamidine (which is recovered as benzamidine)15 and IV-sulfinyl-p-toluenesulfonamide (which evolves sulfur dioxide in the process).16 Irradiation with UV light in the presence of oxygen effects the same reaction, but has not been used on a preparative scale.17... 

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