Thiocyanogen number

This method gives an approximately 0.1N solution and retains its strength for about 8 days. It has been utilized for the purpose of evaluating the amount of unsaturation in various fats and oils.6 The solution has also been used to determine thiocyanogen numbers for resins.7... 

For the determination of the thiocyanogen number of fats and oils, see G. S. Jamieson, Vegetable Fats and Oils. New York Reinhold Publishing Corporation, 1943, page 397. 

Silver thiocyanate, AgCNS.—Solutions of thiocyanates precipitate the thiocyanate from silver solutions. It is a white, cheese-like precipitate, soluble in excess of thiocyanate solution. At 25° C. its solubility is 108 x 10-6 gram-molecule per litre of water.3 It forms a number of double salts with potassium thiocyanate 4 and with bromine in organic solvents it yields a solution of thiocyanogen, (CNS)2-5... 

Thiocyanogen value Vsl- a-no-jon val-(i)yii. Measure of the number of single double bonds in a substance, for example, an oil. Whereas thiocyanogen is selective in its action, adding on to isolated double bonds only, iodine is not selective and thus a combination of both thiocyanogen and iodine values provides a means of assessing quantitatively the different types of unsaturated components in a material. 

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