Thiocyanates thiosulfates

Care must be exercised in using sodium nitrite near other chemicals. It is incompatible with ammonium salts, thiocyanates, thiosulfates, and strong reducing agents. In acid solutions, sodium nitrite evolves toxic NO in the presence of secondary amines it can form nitrosamines which are suspected carcinogens. 

Silica, arsenate, sulfide, thiocyanate, thiosulfate, fluoride, chloride, and iron (II) interfere in the test. Most interferences are observed at high concentrations (>50 mg/L). Silica interference is removed by oxidation with Br water. 

Polarizable Iodide, thiocyanate, thiosulfate, chromate, molybdate, tungstate. 

Light yellow, odorless powder slowly darkened by light. Crystals are hexagonal Or cubic, d 5.67 mp 552. Practically insol in water (0.03 mg/l) in acid (except coned HI in which it dissolves readily on heating) in ammonium carbonate. Freely sol in solns of alkali cyanides or iedides 35 mg dissolve in a liter of 10% ammouia appreciably sol in coned solns of alkali bromides, chlorides, thiocyanates, thiosulfates, mercuric and silver nitrates. It is slowly attacked by boiling coned acids, but not affected by hot solns of alkali hydroxides. 

Incompatibilities and Reactivities Acetates, halogens, thiocyanates, thiosulfates [Note May polymerize upon storage.] ... 

Sulfur ignites at about 260 C (data as low as 190°C pertain to sulfur flowers) and burns to sulfur dioxide (SOg), but some trioxide (SO3) may appear, especially in the presence of iron oxides or other catalysts. Among minor products, sulfide, thiocyanate, thiosulfate, and sulfate may occur in alkaline residues. 

The S—S linkage of sulfenyl thiocyanates, thiosulfates (92), and Bunte salts (93) are also susceptible to cleavage by soft bases. 

Most simple inorganic cations and anions are transparent in the UV, but the larger, more polarizable anions absorb UV radiation, absorbing more strongly at shorter wavelengths. Absorbances at 200-210 nm are sufficiently strong to detect bromide, iodide, nitrate, nitrite, thiocyanate, thiosulfate, and chromate. Carboxylate ions absorb satisfactorily below 215 nm. 

Direct detection has gained great significance in determination of nitrite and nitrate,as well as bromide and iodide in the presence of high chloride concentrations. Moreover, chromate, sulfide, thiocyanate, thiosulfate, and selected metal chloro- and cyano-complexes can be determined by means of this method. 

Thiophosphoryl compounds, mercaptoacetic acid, thiourea and its derivatives, thiocyanate, thiosulfate azide, 0.05-0.1 M iodine 0.08-180 [8]... 

AS 16 High Hydrophobic anions (iodide, thiocyanate, thiosulfate, perchlorate), polyphosphates, polycarbo lates... 

The velocity of the Fe(CNS)3-Na2S203 reaction depends on variations in the concentration ratios of iron thiocyanate thiosulfate, on the acid content, on the temperature. Aluminum, zinc, nickel, and especially arsenic retard the reaction. 

Sulfide, sulfite, thiocyanate, thiosulfate — CE UV Direct Indirect Conductivity detection Amperometric detection Water sample of an open-pit Mining Lake [3]... 

Ammonium Thiocyanato Hydrochloric Acid Ammonium Thiocyanate Thiosulfate ... 

The absorption reactions are those of H2S and HCN combining with ammonia to form ammonium bisulfide and ammonium cyanide, followed by the oxidation of the ammonium bisulfide by the naphthoquinone (NQ) to form elemental sulfur and the naphthohydro-quinone (H2NQ). The reactions with oxygen take place in the regenerator and lead to the formation of NQ, thiocyanate, thiosulfate, and sulfate. Part of the elemental sulfur reacts with the available NH4CN in the oxidizer to produce NH4SCN. 

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