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Alkali Metal Hydroxide
The alkali hydroxides are a class of chemical compounds which are composed of an alkali metal cation and the hydroxide anion (). The alkali hydroxides are: *Lithium hydroxide (LiOH) *Sodium hydroxide (NaOH) *Potassium hydroxide (KOH) * Rubidium hydroxide (RbOH) * Caesium hydroxide (CsOH) * Francium hydroxide (FrOH) Production Alkali hydroxides are formed in the reaction between alkali metals and water. A typical school demonstration demonstrates what happens when a piece of an alkali metal is introduced to a bowl of water. A vigorous reaction occurs, producing hydrogen gas and the specific alkali hydroxide. For example, if sodium is the alkali metal: : Sodium hydroxide is an important industrial chemical, where it is produced by the chloralkali process. Properties and uses The alkali metal hydroxides form white crystals that are hygroscopic and readily soluble in water, generating large amounts of heat upon dissolution. The solubility increases down the column as the alkali m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption (chemistry), absorption or adsorption from the surrounding Natural environment, environment, which is usually at normal or room temperature. If water molecules become suspended among the substance's molecules, adsorbing substances can become physically changed, e.g. changing in volume, boiling point, viscosity or some other physical characteristic or property of the substance. For example, a finely dispersed hygroscopic powder, such as a salt, may become clumpy over time due to collection of moisture from the surrounding environment. ''Deliquescent'' materials are sufficiently hygroscopic that they dissolve in the water they absorb, forming an aqueous solution. Hygroscopy is essential for many plant and animal species' attainment of hydration, nutrition, reproduction and/or seed dispersal. Biological evolution created hygroscopic solutions for water harvesting, filament tensile strength, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsanide
An arsinide, arsanide, dihydridoarsenate(1−) or arsanyl compound is a chemical derivative of arsine, where one hydrogen atom is replaced with a metal or cation. The arsinide ion has formula . It can be considered as a ligand with name or arsanido. Few chemists study arsanyl compounds, as they are both toxic and unstable. The IUPAC names are arsanide and dihydridoarsenate(1−). For the ligand the name is arsanido. The neutral group is termed arsanyl. Formation Alkali metal arsinides can form by bubbling arsine through a liquid ammonia solution of alkali metal such as sodium, potassium or alkaline earth metal such as calcium. Arsinides are also formed when arsine reacts with thin layers of alkali metals. The arsine may reduce some compounds to metals, so for example an attempt to make an indium arsinide results in metallic indium. Reactions When heated, metal hydrogen arsinide and metal dihydrogen arsinide compounds lose hydrogen to become a metal arsenide: : With lithium dih ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphanide
Phosphanides are chemicals containing the H2sup>− anion. This is also known as the phosphino anion or phosphido ligand. The IUPAC name can also be dihydridophosphate(1−). It can occur as a group phosphanyl -PH2 in organic compounds or ligand called phosphanido, or dihydridophosphato(1−). A related substance has PH2−. Phosphinidene (PH) has phosphorus in a −1 oxidation state. As a ligand PH2 can either bond to one atom or be in a μ2-bridged ligand across two metal atoms. With transition metals and actinides, bridging is likely unless the metal atom is mostly enclosed in a ligand. In phosphanides, phosphorus is in the −3 oxidation state. When phosphanide is oxidised, the first step is phosphinite ( 2POsup>−). Further oxidation yields phosphonite ( PO2sup>2−) and phosphite ( O3sup>3−). The study of phosphine derivatives is unpopular, because they are unstable, poisonous and malodorous. Formation Alkali metal phosphanides can be made from phosphine and the me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azanide
Azanide is the IUPAC-sanctioned name for the anion . The term is obscure; derivatives of are almost invariably referred to as amides, despite the fact that amide also refers to the Organic chemistry, organic functional group –. The anion is the conjugate base of ammonia, so it is formed by Ammonia#Self-dissociation, the self-ionization of ammonia. It is produced by deprotonation of ammonia, usually with strong bases or an alkali metal. Azanide has a H–N–H bond angle of 104.5°. Alkali metal derivatives The alkali metal derivatives are best known, although usually referred to as alkali metal amides. Examples include lithium amide, sodium amide, and potassium amide. These salt-like solids are produced by treating liquid ammonia with strong bases or directly with the alkali metals (blue liquid ammonia solutions due to the solvated electron): :, where M = Li, Na, K Silver(I) amide () is prepared similarly. Transition metal complexes of the amido ligand are often produced by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroselenide
Sodium hydroselenide is an inorganic compound with the chemical formula . It is a salt of hydrogen selenide. It consists of sodium cations and hydroselenide anions . Each unit consists of one sodium, one selenium, and one hydrogen atom. Sodium hydroselenide is a selenium analog of sodium hydroxide NaOH. Production Sodium hydroselenide can be made by reducing selenium with sodium borohydride: : Alternatively it can be made from sodium ethoxide exposed to hydrogen selenide: : Sodium hydroselenide is not made for storage, instead it is used immediately after production in a fume hood thanks to the appalling odour of hydrogen selenide. Properties Sodium hydroselenide dissolves in water or ethanol. In humid air sodium hydroselenide is changed to sodium polyselenide In chemistry, a polyselenide usually refers to anions of the formula (Sen)2−, where Se is the Chemical symbol, atomic symbol for the element selenium. Many main group and transition metals form complexes with polyse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrosulfide
Bisulfide (or bisulphide in British English) is an inorganic anion with the chemical formula HS− (also written as SH−). It contributes no color to bisulfide salts, and its salts may have a distinctive putrid smell. It is a strong base. Bisulfide solutions are corrosive and attack the skin. It is an important chemical reagent and an industrial chemical, mainly used in paper pulp industry (Kraft process), textiles, synthetic flavors, coloring brasses, and iron control. Properties A variety of salts are known, including sodium hydrosulfide and potassium hydrosulfide. Ammonium hydrosulfide, a component of "stink bombs" has not been isolated as a pure solid. Some compounds described as salts of the sulfide dianion contain primarily hydrosulfide. For example, the hydrated form of sodium sulfide, nominally with the formula , is better described as . Aqueous bisulfide absorbs light at around 230 nm in the UV–visible spectrum. Using this approach, bisulfide has been de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroperoxide
Hydroperoxides or peroxols are Chemical compound, compounds of the form ROOH, where R stands for any group, typically Organic compound, organic, which contain the hydroperoxy functional group (). Hydroperoxide also refers to the hydroperoxide anion () and its Salt (chemistry), salts, and the neutral hydroperoxyl, hydroperoxyl radical (•OOH) consist of an unbond hydroperoxy group. When R is organic, the compounds are called organic hydroperoxides. Such compounds are a subset of organic peroxides, which have the formula ROOR. Organic hydroperoxides can either intentionally or unintentionally initiate explosive polymerisation in materials with saturated bond, saturated chemical bonds. Properties The bond length in peroxides is about 1.45 Ångström, Å, and the angles (R = Hydrogen, H, Carbon, C) are about 110° (water-like). Characteristically, the dihedral angles are about 120°. The bond is relatively weak, with a bond dissociation energy of , less than half the strength ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide Scrubber
A carbon dioxide scrubber is a piece of equipment that absorbs carbon dioxide (CO2). It is used to treat exhaust gases from industrial plants or from exhaled air in life support systems such as rebreathers or in spacecraft, submersible craft or airtight chambers. Carbon dioxide scrubbers are also used in controlled atmosphere (CA) storage and carbon capture and storage processes. Technologies Amine scrubbing The primary application for CO2 scrubbing is for removal of CO2 from the exhaust of coal- and gas-fired power plants and from the enclosed atmosphere of nuclear submarines. The technology being involves the use of various amines, e.g. monoethanolamine. Cold solutions of these organic compounds bind CO2, but the binding is reversed at higher temperatures: :CO2 + 2 ↔ + , this technology has only been lightly implemented in coal-fired power plants because of capital costs of installing the facility and the operating costs of utilizing it. However, the technology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desiccant
A desiccant is a hygroscopic substance that is used to induce or sustain a state of dryness (desiccation) in its vicinity; it is the opposite of a humectant. Commonly encountered pre-packaged desiccants are solids that absorb water. Desiccants for specialized purposes may be in forms other than solid, and may work through other principles, such as chemical bonding of water molecules. They are commonly encountered in foods to retain crispness. Industrially, desiccants are widely used to control the level of water in gas streams. Types of desiccants Although some desiccants are chemically inert, others are extremely reactive and require specialized handling techniques. The most common desiccant is silica gel, an otherwise inert, nontoxic, water-insoluble white solid. Tens of thousands of tons are produced annually for this purpose. Other common desiccants include activated charcoal, calcium sulfate, calcium chloride, and molecular sieves (typically, zeolites). Desicc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saponification
Saponification is a process of cleaving esters into carboxylate salts and Alcohol (chemistry), alcohols by the action of aqueous alkali. Typically aqueous sodium hydroxide solutions are used. It is an important type of alkaline hydrolysis. When the carboxylate is long chain, its salt is called a soap. The saponification of ethyl acetate gives sodium acetate and ethanol: : Saponification of fats Vegetable oils and animal fats are the traditional materials that are saponified. These greasy materials, triesters called triglycerides, are usually mixtures derived from diverse fatty acids. In the traditional saponification, the triglyceride is treated with lye, which cleaves the ester bonds, releasing fatty acid salts (soaps) and glycerol. In one simplified version, the saponification of stearin gives sodium stearate. : This process is the main industrial method for producing glycerol (). Some soap-makers leave the glycerol in the soap. Others precipitation (chemistry), precipitate t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drain Cleaner
A drain cleaner, also known as drain opener, refers to a person, device, or product used to unblock sewer pipes or clear clogged wastewater drains. This term typically applies to chemical, enzymatic, or mechanical tools such as commercial chemical cleaners, plumber's snakes, drain augers, bio-enzyme solutions, or toilet plungers. In some contexts, it may also refer to a plumber or professional who specializes in drain cleaning and maintenance. Chemical drain cleaners, plungers, handheld drain augers, and air burst drain cleaners are typically used to address clogs in single drain, such as sinks, toilets, tubs, or shower drains. These tools are effective at removing soft obstructions like hair and grease that accumulate near the drain inlet. However, excessive use of chemical drain cleaners can lead to pipe damage. In contrast, enzymatic drain cleaners rely on natural enzymes to break down organic matter such as grease, hair, and food particles, offering a more environmentally fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
