Ammonium NH4SCN

FIGURE 6.9 The endothermic reaction between ammonium thiocyanate, NH4SCN, and barium hydroxide octahydrate, Ba(0H)2-8H20, absorbs a lot of heat and can cause water vapor in the air to freeze on the outside of the beaker. 

Procedure Pipette 25 ml of a standard 0.1 N AgN03 solution into a glass-stoppered flask (iodine-flask), dilute with 50 ml of DW, add to it 2 ml of nitric acid and 2 ml of ferric ammonium sulphate solution and titrate with ammonium solution to the first appearance of red-brown colour. Each ml of 0.1 N silver nitrate is equivalent to 0.007612 g of NH4SCN. 

A.3.5.6 Preparation of 20 Percent Solution of Ammonium Thiocyanate. Dissolve 60g of reagent grade ammonium thiocyanate (NH4SCN) in 240ml of distd w. Filter until clear and store 4.4.3.5.7 Preparation of 6N Hydrochloric Acid. 

Physical Properties. Ammonium thiocyanate [1762-95-4], NH4SCN, is a hygroscopic crystalline solid which deliquesces at high humidities (375,376). It melts at 149°C with partial isomerization to thiourea. It is soluble in water to the extent of 65 wt % at 25°C and 77 wt % at 60°C. It is also soluble to 35 wt % in methanol and 20 wt % in ethanol at 25°C. It is highly soluble in liquid ammonia and liquid sulfur dioxide, and moderately soluble in acetonitrile. 

L) 0.01 N ammonium thiocyanate, 0.01 N NH4SCN add 5 mL of standard volumetric concentrate ammonium thiocyanate solution [obtainable from chemical suppliers, for example, from Thomas Scientific as ACCULUATE (Anachemia)] to 1 L water... 

Ammonium Thiocyanate (50%) Transfer 500 g of NH4SCN, ACS certified, to a 1-L volumetric flask dissolve in about 600 mL of water, warming if necessary and dilute to volume. 

Ammonium Thiocyanate TS (1 A) Dissolve 8 g of ammonium thiocyanate (NH4SCN) in sufficient water to make 100 mL. 

Ammonium Thiocyanate, 0.1 N (7.612 g NH4SCN per 1000 mL) Dissolve about 8 g of ammonium thiocyanate (NH4SCN) in 1000 mL of water, and standardize by titrating the solution against 0.1 N Silver Nitrate as follows Transfer about 30 mL of 0.1 N Silver Nitrate, accurately measured, into a glass-stoppered flask. Dilute with 50 mL of water, then add 2 mL of Ferric Ammonium Sulfate TS and 2 mL of nitric acid, and titrate with the ammonium thiocyanate solution to the first appearance of a red-brown color. Calculate the normality, and, if desired, adjust the solution to exactly 0.1 A. If desired, 0.1 N Ammonium Thiocyanate may be replaced by 0.1 A potassium thiocyanate where the former is directed in various tests and assays. 

Ammonium tetrathiocyanatomercurate(II) (0 3m). Dissolve 9 g ammonium thiocyanate, NH4SCN, and 8 g mercury(II) chloride, HgCl2, in water and dilute to 100 ml. 

Ammonium thiocyanate (saturated solution in acetone). Shake 1 g ammonium thiocyanate, NH4SCN, with 5 ml acetone, and use the clear supernatant liquid for the tests. 

Cobalt(II) thiocyanate (10%). Dissolve 1 g cobalt acetate tetrahydrate CO(CH3COO)2.4H20 in 5 ml water. In a separate vessel dissolve 1 g ammonium thiocyanate, NH4SCN, in 5 ml water, and mix the two solutions. 

Af Ammonium thiocyanate (NH4SCN) dissolved in water and stored in a brown glass bottle at 4°G... 

Epoxides can be converted directly to episulfides by treatment with NH4SCN and ceric ammonium nitrate.Diazoalkanes, treated with sulfur, give episulfides.It is likely that R2C=S is an intermediate, which is attacked by another molecule of diazoalkane, in a process similar to that shown in 16-46. Thioketones do react with diazoalkanes to give episulfides.Thioketones have also been converted to episulfides with sulfur ylids.Carbenes, such as the dichlorocarbene from CHCI3 and base, react with thioketones to give an... 

Run a blank by sweeping air with a stream of CO2 from an empty flask F, and, while continuing to pass CO2, add 25 ml of glac AcOH, 25ml of 15% HCl soln and 20ml of 0.2N 1103 soln. This is followed by boiling for 5 mins. While the flask is connected to a reflux condenser, cool and titrate with 0.15N ferric ammonium sulfate in the presence of 5 ml of 20% NH4SCN soln Calculation ... 

Ammonium Thiocyanate. Thiocyanic acid ammonium salt ammonium rhodanide ammonium sulfocyanate ammonium sulfocyanide. CH4N3S mol wt 76,12, C 15.73%, H 5.30% N 36.80%, S 42.12%. NH4SCN. The usual grade is 98-99% pure. Prepn Gmetin s. Ammonium (8th ed ) 23, pp 372-383 (1936). 

The analogous ammonixam salt (NH4)3 [Cr(SCN)e] 4 HgO is obtained in the same manner, except that reaction in the solution of NH4SCN and chromium ammonium alum takes place only after a brief period of boiling. 

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