Names | |||
---|---|---|---|
IUPAC name Potassium cyanate | |||
Identifiers | |||
3D model (JSmol) | |||
3560091 | |||
ChEBI | |||
ChEMBL | |||
ChemSpider | |||
ECHA InfoCard | 100.008.798 | ||
EC Number |
| ||
21361 | |||
KEGG | |||
PubChem CID | |||
RTECS number |
| ||
UNII | |||
CompTox Dashboard (EPA) | |||
| |||
| |||
Properties | |||
KOCN | |||
Molar mass | 81.1151 g/mol | ||
Appearance | white, crystalline powder | ||
Density | 2.056 g/cm3 | ||
Melting point | 315 °C (599 °F; 588 K) | ||
Boiling point | ~700 °C (1,292 °F; 973 K) decomposes | ||
75 g/100 mL | |||
Solubility | very slightly soluble in alcohol | ||
Structure | |||
tetragonal | |||
Hazards | |||
GHS labelling: | |||
Warning | |||
H302 | |||
P264, P270, P301+P312, P330, P501 | |||
NFPA 704 (fire diamond) | |||
Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 841 mg/kg (oral, rat) | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Potassium cyanate is an inorganic compound with the formula KOCN (sometimes denoted KCNO [1] ). It is a colourless solid. It is used to prepare many other compounds including useful herbicide. Worldwide production of the potassium and sodium salts was 20,000 tons in 2006. [2]
The cyanate anion is isoelectronic with carbon dioxide and with the azide anion, being linear. The C-N distance is 121 pm, about 5 pm longer than for cyanide. [3] [4] Potassium cyanate is isostructural with potassium azide. [5]
The potassium and sodium salts can be used interchangeably for the majority of applications. Potassium cyanate is often preferred to the sodium salt, which is less soluble in water and less readily available in pure form.
Potassium cyanate is used as a basic raw material for various organic syntheses, including, urea derivatives, semicarbazides, carbamates and isocyanates. For example, it is used to prepare the drug hydroxyurea. It is also used for the heat treatment of metals (e.g., Ferritic nitrocarburizing). [2] [7]
Potassium cyanate has been used to reduce the percentage of sickled erythrocytes under certain conditions and has also increased the number of deformalities. In an aqueous solution, it has prevented irreversibly the in vitro sickling of hemoglobins containing human erythrocytes during deoxygenization. Veterinarians have also found potassium cyanate useful in that the cyanate salts and isocyanates can treat parasite diseases in both birds and mammals. [8]
KOCN is prepared by heating urea with potassium carbonate at 400 °C:
The reaction produces a liquid. Intermediates and impurities include biuret, cyanuric acid, and potassium allophanate (KO2CNHC(O)NH2), as well as unreacted starting urea, but these species are unstable at 400 °C. [2]
Protonation gives a 97:3 mixture (at room temperature) of two tautomers, HNCO (isocyanic acid) and NCOH (cyanic acid). This mixture is stable at high dilution but trimerizes on concentration to give cyanuric acid.
Potassium carbonate crystals are destroyed by the melting process so that the urea can react with almost all potassium ions to convert to potassium cyanate at a higher rate than when in the form of a salt. This makes it easier to reach higher purities above 95%. It can also be made by oxidizing potassium cyanide at a high temperature in the presence of oxygen or easily reduced oxides, such as lead, tin, or manganese dioxide, and in aqueous solution by reacting with hypochlorites or hydrogen peroxide. Another way to synthesize it is to allow an alkali metal cyanide to react with oxygen in nickel containers under controlled conditions. It can be formed by the oxidation of ferrocyanide. Lastly, it can be made by heating potassium cyanide with lead oxide. [9]
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word carbonate may also refer to a carbonate ester, an organic compound containing the carbonate groupO=C(−O−)2.
Carbon compounds are defined as chemical substances containing carbon. More compounds of carbon exist than any other chemical element except for hydrogen. Organic carbon compounds are far more numerous than inorganic carbon compounds. In general bonds of carbon with other elements are covalent bonds. Carbon is tetravalent but carbon free radicals and carbenes occur as short-lived intermediates. Ions of carbon are carbocations and carbanions are also short-lived. An important carbon property is catenation as the ability to form long carbon chains and rings.
Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colorless and odorless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element in air. Because of the volatility of nitrogen compounds, nitrogen is relatively rare in the solid parts of the Earth.
Some chemical authorities define an organic compound as a chemical compound that contains carbon–hydrogen or carbon–carbon bonds; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as halides of carbon without carbon-hydrogen and carbon-carbon bonds, and certain compounds of carbon with nitrogen and oxygen.
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions.
Sodium cyanide is a poisonous compound with the formula NaCN. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.
Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.
In chemistry, azide is a linear, polyatomic anion with the formula N−3 and structure −N=N+=N−. It is the conjugate base of hydrazoic acid HN3. Organic azides are organic compounds with the formula RN3, containing the azide functional group. The dominant application of azides is as a propellant in air bags.
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds—that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as inorganic chemistry.
Sodium azide is an inorganic compound with the formula NaN3. This colorless salt is the gas-forming component in some car airbag systems. It is used for the preparation of other azide compounds. It is an ionic substance, is highly soluble in water, and is very acutely poisonous.
Pseudohalogens are polyatomic analogues of halogens, whose chemistry, resembling that of the true halogens, allows them to substitute for halogens in several classes of chemical compounds. Pseudohalogens occur in pseudohalogen molecules, inorganic molecules of the general forms Ps–Ps or Ps–X, such as cyanogen; pseudohalide anions, such as cyanide ion; inorganic acids, such as hydrogen cyanide; as ligands in coordination complexes, such as ferricyanide; and as functional groups in organic molecules, such as the nitrile group. Well-known pseudohalogen functional groups include cyanide, cyanate, thiocyanate, and azide.
The cyanate ion is an anion with the chemical formula OCN−. It is a resonance of three forms: [O−−C≡N] (61%) ↔ [O=C=N−] (30%) ↔ [O+≡C−N2−] (4%).
Isocyanic acid is a chemical compound with the structural formula HNCO, which is often written as H−N=C=O. It is a colourless, volatile and poisonous substance, with a boiling point of 23.5 °C. It is the predominant tautomer and an isomer of cyanic acid (aka. cyanol).
Cyanogen bromide is the inorganic compound with the formula (CN)Br or BrCN. It is a colorless solid that is widely used to modify biopolymers, fragment proteins and peptides, and synthesize other compounds. The compound is classified as a pseudohalogen.
Hexafluorosilicic acid is an inorganic compound with the chemical formula H
2SiF
6. Aqueous solutions of hexafluorosilicic acid consist of salts of the cation and hexafluorosilicate anion. These salts and their aqueous solutions are colorless.
Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides. The compound has a low melting point relative to most other inorganic salts.
The chemical element nitrogen is one of the most abundant elements in the universe and can form many compounds. It can take several oxidation states; but the most common oxidation states are -3 and +3. Nitrogen can form nitride and nitrate ions. It also forms a part of nitric acid and nitrate salts. Nitrogen compounds also have an important role in organic chemistry, as nitrogen is part of proteins, amino acids and adenosine triphosphate.
Potassium azide is the inorganic compound having the formula KN3. It is a white, water-soluble salt. It is used as a reagent in the laboratory.
Sodium cyanate is the inorganic compound with the formula NaOCN. A white solid, it is the sodium salt of the cyanate anion.
The phosphaethynolate anion, also referred to as PCO, is the phosphorus-containing analogue of the cyanate anion with the chemical formula [PCO]− or [OCP]−. The anion has a linear geometry and is commonly isolated as a salt. When used as a ligand, the phosphaethynolate anion is ambidentate in nature meaning it forms complexes by coordinating via either the phosphorus or oxygen atoms. This versatile character of the anion has allowed it to be incorporated into many transition metal and actinide complexes but now the focus of the research around phosphaethynolate has turned to utilising the anion as a synthetic building block to organophosphanes.