Cuprous thiocyanate

Thiocyanates are rather stable to air, oxidation, and dilute nitric acid. Of considerable practical importance are the reactions of thiocyanate with metal cations. Silver, mercury, lead, and cuprous thiocyanates precipitate. Many metals form complexes. The deep red complex of ferric iron with thiocyanate, [Fe(SCN)g] , is an effective iadicator for either ion. Various metal thiocyanate complexes with transition metals can be extracted iato organic solvents. 

Cupro-. cuprous, copper(I), cupro-. -chlorid, n. cuprous chloride, copper(I) chloride, -cy-aniir, n. cuprous cyanide, copper(I) cyanide cuprocyanide, cyanocuprate(I). -jodid, n. cuprous iodide, copper(I) iodide, -mangan, n. cupromanganese. -oxyd, n. cuprous oxide, copper(I) oxide, -salz, n. cuprous salt, cop-per(I) salt, -suifocyantir, n. cuprous thiocyanate, copper (I) thiocyanate, -verbin-dUDg, /. cuprous compound, copper(I) compound. 

Cuprous thiocyanate [18223-42-2] M 121.6. Purified as for cuprous iodide but using aq NaSCN. 

The reactions of thiocyanogen may roughly be divided into two types (1) Reactions in which the radical combines directly with metals to form the corresponding thiocyanates, and with cuprous thiocyanate to form the cupric salt. (2) Reactions in which a substitution is effected for example, with aniline, dimethylaniline and phenol, the corresponding jj-thiocyano-derivatives and thiocyanie acid are formed.1... 

Both cupric and cuprous thiocyanates may be obtained by precipitation. The former, which forms as a black precipitate when excess of thiocyanate is added to a copper salt, is unstable, and if allowed to remain under water, loses thiocyanic acid and forms the cuprous salt.5 The latter is precipitated as a white powder by the addition of a soluble thiocyanate to a solution of copper sulphate in the presence of sulphurous acid. 

Yolumetrically, thiocyanate is estimated by Volhard s method, which involves titration with standard silver nitrate solution containing nitric acid, ferric alum being used as indicator. Cuprous thiocyanate dissolved in ammonium hydroxide solution and acidified with dilute sulphuric acid may be titrated with permanganate.6 An iodometrie method has also been described.7... 

Cuprous thiocyanate, CuCNS.—The thiocyanate is produced by dissolving cuprous oxide or carbonate in thiocyanic acid, and by the interaction of solutions of potassium thiocyanate and a cupric salt in presence of a reducer, such as ferrous sulphate or sulphurous acid.2 It is a white substance, its solubility at 18° C. being 0 23 mg. in 1 litre of water.3 It dissolves in ammonium hydroxide and concentrated hydrochloric acid, and also in concentrated nitric acid with formation of cupric sulphate. It is employed in the preparation of aromatic thiocyanates.4... 

Cupric thiocyanate, Cu(CNS)2.—The thiocyanate is formed as a velvet-black precipitate by adding basic cupric carbonate or cupric hydroxide to a solution of thiocyanic acid, and by the interaction of potassium thiocyanate and concentrated solutions of cupric salts.8 It is very unstable, being transformed by contact with water into cuprous thiocyanate.9 With ammonium hydroxide it yields blue, aeicular crystals of ammonio-cupric ihiocyanaie, Cu(CNS)2,2NHs, also produced by dissolving cupric hydroxide in ammonium thiocyanate.10... 

Meitzendorff, Pogg. Annalen, 1842, 56,63. Soderbaok (Annalen, 1919,419,217) prepared it by the action of thiooyanogen (p. 320) in ether solution on cuprous thiocyanate. 

There is a great variety of quantitative methods available for the estimation of copper. Gravimetrically it is estimated as cupric oxide, obtained by ignition of the precipitated hydroxide by precipitation as sulphide, and ignition in an atmosphere of hydrogen to cuprous sulphide by precipitation as cuprous thiocyanate, CuCNS, this salt being either weighed directly, or converted into cuprous sulphide and by electrolytic... 

Falciola, Giorn. Chim. Jnd. Applic., 1921, 3, 354. The turbidity is due to cuprous thiocyanate. 

Other stable cuprous compounds are the insoluble substances cuprous oxide, Cu.,0 (red), cuprous sulfide, Cu. S (black), cuprous cyanide, CuCN (white), and cuprous thiocyanate, CuSCN (white). 

Caswell No. 266A Copper thiocyanate Copper(1+) thiocyanate Cuprous thiocyanate Cusyd EINECS 214-183-1 EPA Pesticide Chemical Code 025602 Thiocyanic acid, coppe (1 ) salt. Used as marine anti-fouling agent. Solid d = 2.85 insoluble in H2O, organic solvents. Mechema Chemicals Ltd. 

Cuprous thiocyanate-charcoal Ar. thiocyanates from halides... 

Copper salts, which give a red-brown coloration or precipitate of Cu(CNS)2, should be removed as white acid-insoluble cuprous thiocyanate by the addition of alkali sulfite. 

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