Тиоцианат аммония

Description

Ammonium thiocyanate (ammonium thiocyanide) is the ammonium salt of thiocyanic acid, CAS 1762-95-4, gross formula CHNS,H3N (NH4SCN).

Basic Attributes

• CAS No.: 1762-95-4 (additional numbers 1189-67-9, 1674-80-2, 14314-30-8, 15268-45-8, 92568-90-6, 101218-28-4, 113506-91-5, 1147550-11-5)
• Chemical formula: CHNS,H3N
• Molecular Weight: 76.12090

Chemical nature

The thiocyanate anion SCN⁻ is a pseudohalide, structurally and chemically similar in many ways to chloride and bromide ions: it forms poorly soluble salts with silver and mercury, and is prone to complex formation with transition metal ions (iron, cobalt, copper) with a characteristic coloring of solutions, which underlies many analytical techniques based on it. The ammonium cation gives the salt good solubility in water and a noticeable endothermic effect during dissolution, also characteristic of ammonium nitrate and other ammonium salts, which reduces the temperature of the solution by tens of degrees upon rapid dissolution.

Scope of application

Ammonium thiocyanate, like the related sodium thiocyanate, is used in the textile industry as a solvent for polyacrylonitrile when spinning synthetic fibers, in photography as a component of fixing and auxiliary compositions, in agriculture as a defoliant and herbicide, in chemical analysis as a reagent for the determination of iron(III) by the characteristic blood-red color of the solution and in volumetric analysis (rhodanometry, Volhard's method for the determination of halides and silver), as well as as a starting material for the production of other thiocyanates and thiourea derivatives. A component of cold heating pads and cooling mixtures due to a noticeable endothermic effect when dissolved in water, a property widely used in thermochemistry demonstration experiments.

Synonyms

Also found in sources as ammonium rhodanate, thiocyanate, ammonium isothiocyanate, ammonium sulfocyanate, ammonium cyanide sulfide (NH4CNS) - historical and regional designations for the same compound from different chemical suppliers and in different technical documentation.

General precautions

Like other thiocyanates, the compound can release toxic volatile products when in contact with acids, similar to sodium thiocyanate and barium thiocyanate - work with gloves, safety glasses and ventilation, keep away from acids and strong oxidizing agents.

What is not transferred from the dump

The source dump for this position contains only a line with molecular weight - data on appearance, density, melting and boiling points, solubility, LD50 toxicity and GHS phrase block are not present in the source. These parameters are not found in the dump and are not inferred in accordance with the “don't invent anything” rule; Application information is based on the general chemistry of alkali and ammonium thiocyanates documented for related compounds of the same batch (sodium thiocyanate, barium thiocyanate).