Potassium Rodanide (according to the modern IUPAC nomenclature- potassium thiocyanate) - crystals, colorless and odorless; in the fine state they gain white color. The substance has a bitter sharp taste, is poisonous. Potassium Rodanide is highly soluble in many solvents such as water, amyl alcohol, and ethanol.
Receiving
The substance is obtained only by chemical means.to isolate it from natural sources (human blood and saliva) is extremely expensive. In order to synthesize potassium rhodanide, it is necessary to mix solutions of ammonium thiocyanate and potassium hydroxide (a trivial name is caustic potassium).
The experience is carried out under the umbrella, becauseexcreted ammonia can cause chemical burns and poisoning; then the purified solution is filtered and the residue is evaporated until the crystals of the required substance are obtained. With a product yield of up to seventy percent and a fairly pure sample of ammonium rhodium, this method is very effective.
Another method consists in fusing sulfur with potassium cyanide, however, this method of producing potassium thiocyanate is very dangerous due to the high toxicity of cyanide.
Application
Potassium rodanide, its derivatives and solutions with different concentrations in several industries are used. For example:
- Textile industry.
- Film photography.
- Organic synthesis.
- Analytical chemistry.
Areas of use
- In the textile industry. Potassium Rodanide solution is used for dressing fabrics, such as silk, during dyeing and processing in order to preserve the original properties of the material.
- In organic synthesis.Some organic substances, such as thiourea, synthetic mustard oil, and various dyes, are synthesized from potassium rhodanide. It also produces other thiocyanates, for example, rodanide copper-2.
- In analytical chemistry, the solution of potassium rhodanideused to determine ferric cations in a substance. An illustrative example is the reaction in which potassium rhodanide and ferric chloride-3, also called “blood from water,” are involved, in which the purple-red hexacyanoferrate 3 of potassium is formed; the trivial name is red blood salt. Thiocyanates are also used to separate rare metals like thorium and lanthanum. Potassium Rodanide and chloride of jelly recently helps in obtaining artificial blood for filming, but this method goes by the wayside due to the introduction of computer graphics into filmmaking.
- In agriculture, strong insecticides are obtained from thiocyanate solutions. There are two possible reactions:
- The first is to obtain thiocyan gas by removing potassium from salt; Rodan is quite a dangerous gas for all living organisms and is rarely used.
- The second is the dissolution of potassium rhodanide, collectionreleased during hydrolysis of cyanic acid and oxidation of the resulting substance to cyan. Cyan is not less toxic, but heavier gas than Rodan, and therefore is more often used as an insecticide.
Potassium Rodanide is a toxic substance, the lethal dose of which is about 0.9 grams of a substance per kilogram of a person’s weight when the compound is taken orally.
Availability
Роданид калия можно купить в любом магазине chemical reagents, but in small quantities due to fairly high toxicity. The average price of the reagent is four hundred rubles per kilogram, the sale is most often limited to two kilograms per person.
Security
Due to its toxicity, potassium rhodanide must be stored in special conditions for safety requirements when handling toxic substances:
- Crystals and solutions of potassium rhodanide are strictly prohibited to be ingested, and it is highly undesirable that solutions with a high concentration of the basic substance come into contact with the skin.
- Несмотря на то, что препарат ядовит лишь при orally, it is desirable to work with the substance in rubber gloves and a lab coat, as well as with all chemical reagents for the basic safety requirements.
- The substance should be isolated from children and persons who do not have laboratory knowledge, since this can cause unpleasant incidents involving the loss of reagents, improper use and sudden death.
- Since the substance is non-flammable and fairly stablein the air, you can do by storing the substance in the dark. dry closet. High humidity and direct sunlight should be avoided, since deterioration of the reagent may occur as a result of its decomposition into its component parts. Also according to the standard NFPA 704, the following symbols are on the rhombic marking: 3 0 0 W, where 3 (on a blue rhombus) is toxic, 0 (on red and yellow) is combustibility and reactivity, and W is the mark for interaction with water, with which is the release of poisonous thiocyanic acid.
And remember, chemical experiments are amazing and unique, but never neglect safety!
