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Potassium Thiosulfate
Potassium thiosulfate, commonly abbreviated KTS, is an inorganic compound with the formula K2S2O3. This salt can form multiple hydrates, such as the monohydrate, dihydrate, and the pentahydrate, all of which are white or colorless solids. It is used as a fertilizer. Formation and reactions Thiosulfate salts are produced by the reaction of sulfite ion with elemental sulfur, and by incomplete oxidation of sulfides. For example, this salt is produced by reacting potassium hydroxide with ammonium hydroxide, sulfur dioxide, and elemental sulfur. Thiosulfates are stable in neutral or alkaline solutions, but not in acidic solutions, due to disproportionation to sulfur dioxide and sulfur: : + 2 H+ → SO2 + "S" + H2O Due to this property, it can sequester metals, especially iron. Thiosulfate reacts with iodine to give tetrathionate, in this case potassium thiosulfate reacts with iodine to produce potassium tetrathionate and potassium iodide: :2 K2 + I2 → K2 + 2 KI Thiosulfate ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Sulfite
Potassium sulfite is the inorganic compound with the formula K2SO3. It is the salt of potassium cation and sulfite anion. It is a white solid that is highly soluble in water. Use Potassium sulfite is widely used for preserving food and beverages. Production and reactions Potassium sulfite is produced by the thermal decomposition of potassium metabisulfite Potassium metabisulfite, K2S2O5, also known as potassium pyrosulfite, is a white crystalline powder with a pungent odour. It is mainly used as an antioxidant or chemical sterilant. As a disulfite, it is chemically very similar to sodium metabi ... at 190°C: :K2S2O5 → K2SO3 + SO2 References Potassium compounds Sulfites {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuric Acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formula . It is a colorless, odorless and viscous liquid that is miscible with water. Pure sulfuric acid does not exist naturally on Earth due to its strong affinity to water vapor; it is hygroscopic and readily absorbs water vapor from the air. Concentrated sulfuric acid is highly corrosive towards other materials, from rocks to metals, since it is an oxidant with powerful dehydrating properties. Phosphorus pentoxide is a notable exception in that it is not dehydrated by sulfuric acid, but to the contrary dehydrates sulfuric acid to sulfur trioxide. Upon addition of sulfuric acid to water, a considerable amount of heat is released; thus the reverse procedure of adding water to the acid should not be performed since the heat released may boi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytotoxicity
Phytotoxicity describes any adverse effects on plant growth, physiology, or metabolism caused by a chemical substance, such as high levels of fertilizers, herbicides, heavy metals, or nanoparticles. General phytotoxic effects include altered plant metabolism, growth inhibition, or plant death. Changes to plant metabolism and growth are the result of disrupted physiological functioning, including inhibition of photosynthesis, water and nutrient uptake, cell division, or seed germination. Fertilizers High concentrations of mineral salts in solution within the plant growing medium can result in phytotoxicity, commonly caused by excessive application of fertilizers. For example, urea is used in agriculture as a nitrogenous fertilizer. However, if too much is applied, phytotoxic effects can result from urea toxicity directly or ammonia production from hydrolysis of urea. Organic fertilizers, such as compost, also have the potential to be phytotoxic if not sufficiently humified, as i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumigants
Fumigation is a method of pest control or the removal of harmful micro-organisms by completely filling an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is used to control pests in buildings (structural fumigation), soil, grain, and produce. Fumigation is also used during the processing of goods for import or export to prevent the transfer of exotic organisms. Structural fumigation targets pests inside buildings (usually residences), including pests that inhabit the physical structure itself, such as woodborers and drywood termites. Commodity fumigation, on the other hand, is also to be conducted inside a physical structure, such as a storage unit, but it aims to eliminate pests from infesting physical goods, usually food products, by killing pests within the container which will house them. Each fumigation lasts for a certain duration. This is because after spraying the pesticides, or fumigants, only the pests around are erad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrous Oxide
Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas, nitrous, or nos, is a chemical compound, an oxide of nitrogen with the formula . At room temperature, it is a colourless non-flammable gas, and has a slightly sweet scent and taste. At elevated temperatures, nitrous oxide is a powerful oxidiser similar to molecular oxygen. Nitrous oxide has significant medical uses, especially in surgery and dentistry, for its anaesthetic and pain-reducing effects. Its colloquial name, "laughing gas", coined by Humphry Davy, is due to the euphoric effects upon inhaling it, a property that has led to its recreational use as a dissociative anaesthetic. It is on the World Health Organization's List of Essential Medicines. It is also used as an oxidiser in rocket propellants, and in motor racing to increase the power output of engines. Nitrous oxide's atmospheric concentration reached 333 parts per billion (ppb) in 2020, increasing at a rate of abo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrification
''Nitrification'' is the biological oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate occurring through separate organisms or direct ammonia oxidation to nitrate in comammox bacteria. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea. Microbiology Ammonia oxidation The oxidation of ammonia into nitrite (also known as nitritation) is performed by two groups of organisms, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). AOB AOB can be found among the Betaproteobacteria and Gammaproteobacteria. Since discovery of AOA in 2005, two isolates have been cultivated: ''Nitrosopumilus maritimus'' and ''Nitrososphaera viennensis''. In soils the most studied AOB belong to the genera ''Nitrosomonas'' and '' Nitrococcus''. AOA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea Ammonium Nitrate
UAN is a solution of urea and ammonium nitrate in water used as a fertilizer. Uan or UAN may also refer to: * Adapa, an alternate name for the first of the Mesopotamian seven sages * Autonomous University of Nayarit ((in Spanish: ), a Mexican public university based in the city of Tepic, Nayarit * Kuan language (Laos), by ISO 639-3 language code * United American Nurses, formerly an American union affiliated with the AFL-CIO * (National Academic Union), a learned society in Italy * Universal Account Number, a 12-digit number allotted to employee who is contributing to the Employees' Provident Fund Organisation of India People * Uan Rasey (1921–2011), an American musician * Mariuti Uan Mariuti Uan (born 22 January 1986) is a sprinter from Kiribati. He was his country's only athlete at the 2005 World Championships in Athletics, running an 11.92 +0.6 personal best. He later competed in the 2006 Commonwealth Games held in Melbourn ... (born 1986), a sprinter from Kiribati * Vik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules () with a carbon dioxide () molecule in the urea cycle. Urea is widely used in fertilizers as a source of nitrogen (N) and is an important raw material for the chemical industry. In 1828 Friedrich Wöhler discovered that urea can be produced from inorganic starting materials, which was an important conceptual milestone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transition Metal
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. They are the elements that can use d orbitals as valence orbitals to form chemical bonds. The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be transition metals as well. Since they are metals, they are lustrous and have good electrical and thermal conductivity. Most (with the exception of group 11 and group 12) are hard and strong, and have high melting and boiling temperatures. They form compounds in any of two or more different oxidation states and bind to a variety of ligands to form coordination complexes that are often coloured. They form many useful alloys and are often employed as catalysts in elemental form or in compounds such as coordination complexes and oxides. Most are strongly param ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Iodide
Potassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are used. In the third world it is also used for treating skin sporotrichosis and phycomycosis. It is a supplement used by people with low dietary intake of iodine. It is administered orally. Common side effects include vomiting, diarrhea, abdominal pain, rash, and swelling of the salivary glands. Other side effects include allergic reactions, headache, goitre, and depression. While use during pregnancy may harm the baby, its use is still recommended in radiation emergencies. Potassium iodide has the chemical formula K I. Commercially it is made by mixing potassium hydroxide with iodine. Potassium iodide has been used medically since at least 1820. It is on the World Health Organization's List of Essential Medicines. Potassium iodide is av ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrathionate
The tetrathionate anion, , is a sulfur oxoanion derived from the compound tetrathionic acid, H2S4O6. Two of the sulfur atoms present in the ion are in oxidation state 0 and two are in oxidation state +5. Alternatively, the compound can be viewed as the adduct resulting from the binding of to SO3. Tetrathionate is one of the polythionates, a family of anions with the formula ''n''(SO3)2sup>2−. Its IUPAC name is ''2-(dithioperoxy)disulfate'', and the name of its corresponding acid is ''2-(dithioperoxy)disulfuric acid''. The Chemical Abstracts Service identifies tetrathionate by the CAS Number 15536-54-6. Formation Tetrathionate is a product of the oxidation of thiosulfate, , by iodine, I2: :2 + I2 → + 2 I− Structure Tetrathionate's structure can be visualized by following three edges of a rectangular cuboid, as in the diagram below. The structure shown is the configuration of in BaS4O6·2H2O and Na2S4O6·2H2O. Dihedral S–S–S–S angles approaching 90° are comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
