CNC1 Cyanogen chloride

CNC1 Cyanogen chloride, 2 90, 93 (CN)2Ni Nickel cyanide, 2 228 C(=NH)(NH2)NHCN Dicya-nodiamide, 3 43... 

Bleaching powder destroys tabun, but it gives rise to cyanogen chloride, CNC1, which is also toxic. 

Thiocyanate is a monovalent polyanion that has the formula SCN-. This anion is rarely found in wastewaters. However, cyanide-containing wastes or waters on contact with sulfides can form thiocyanates. On chlorination, thiocyanate could react with chlorine to form highly toxic cyanogen chloride, CNC1. Thiocyanate in water may be analyzed using 1. colorimetric method and 2. spot test. The latter method is a rapid spot test that can give semiquantitative results. Preserve samples at pH below 2 and refrigerate. 

Thiocyanate reacts with chloramine-T on heating at pH below 8 to form cyanogen chloride, CNC1. The latter forms red color after adding pyridine-barbituric acid reagent. This test is similar to that of cyanide. Therefore, prior to chloramine treatment, the sample is treated with formaldehyde to mask the effect of cyanide. The addition of 4 drops of 37% formaldehyde solution should mask up to 5 to 10 mg CN7L if present in the sample. 

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