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Tetrachlorozincate
Tetrachlorozincate is an anion with the formula . It is a counterion that is often used in conjunction with strong electrophiles. Being dianionic, tetrachlorozincate is not classified as a weakly coordinating anion. On the other hand, being dianionic, tetrachlorozincate facilitates the crystallization of many salts. It has a tetrahedral molecular geometry. A simple example is (ammonium tetrachlorozincate). Zincates are anionic zinc complexes. Related to the preparation of Lucas' reagent, tetrachlorozincates are often generated by combining hydrochloric acid and zinc chloride. A related anion is , in which again Zn(II) adopts a tetrahedral geometry. References {{Reflist Tetrachlorozincates, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Chloride
Zinc chloride is an Inorganic chemistry, inorganic chemical compound with the chemical formula, formula ZnCl2·''n''H2O, with ''n'' ranging from 0 to 4.5, forming water of hydration, hydrates. Zinc chloride, anhydrous and its hydrates, are colorless or white crystalline solids, and are highly Solubility, soluble in water. Five hydrates of zinc chloride are known, as well as four Polymorphism (materials science), polymorphs of anhydrous zinc chloride. All forms of zinc chloride are deliquescent. They can usually be produced by the reaction of zinc or its compounds with some form of hydrogen chloride. Anhydrous zinc compound is a Lewis acid, readily forming complexes with a variety of Lewis bases. Zinc chloride finds wide application in textile processing, flux (metallurgy), metallurgical fluxes, chemical synthesis of organic compounds, such as benzaldehyde, and processes to produce other compounds of zinc. History Zinc chloride has long been known but currently practiced industr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Tetrachlorozincate
Zinc ammonium chloride is the inorganic compound with the formula (NH4)2ZnCl4. It is the ammonium salt of tetrachlorozincate. It used as a flux in the process of hot-dip galvanizing. Uses Steel to be galvanized passes through an acidic cleaning process to remove iron oxide "mill scale". After this process, the surface of the steel is very active and oxide layers begin forming immediately upon exposure to the atmosphere. Zinc ammonium chloride flux in aqueous solution is applied to the steel to reduce any oxides that are formed and/or inhibit them from forming altogether. This allows the molten zinc in the proceeding galvanizing step to maximally adhere to and alloy with the surface of the steel. Precautions Zinc ammonium chloride is a Class 9 hazardous material (Miscellaneous) according to the U.S. DOT. References {{Ammonium salts ammonium chloride Tetrachlorozincates zinc Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrachloronickelate
Tetrachloronickelate is the metal complex with the formula iCl4sup>2−. Salts of the complex are available with a variety of cations, but a common one is tetraethylammonium. When concentrated lithium chloride and nickel chloride solution in water is mixed, only a pentaaquachloro complex is formed: i(H2O)5Clsup>+. However in other organic solvents, or molten salts the tetrachloronickelate ion can form. Nickel can be separated from such a solution in water or methanol, by partitioning it into a cyclohexane solution of amines. Organic ammonium salts of the type (R3NH)2 iCl4are often thermochromic Thermochromism is the property of Chemical substance, substances to change color due to a change in temperature. A mood ring is an example of this property used in a consumer product although thermochromism also has more practical uses, such as b ... (R = Me, Et, Pr). Near room temperature, these salts are yellow , but these solids become blue when heated to near 70 °C. The br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anion
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons. A cation is a positively charged ion with fewer electrons than protons (e.g. K+ ( potassium ion)) while an anion is a negatively charged ion with more electrons than protons (e.g. Cl− ( chloride ion) and OH− ( hydroxide ion)). Opposite electric charges are pulled towards one another by electrostatic force, so cations and anions attract each other and readily form ionic compounds. Ions consisting of only a single atom are termed ''monatomic ions'', ''atomic ions'' or ''simple ions'', while ions consisting of two or more atoms are termed polyatomic ions or ''molecular ions''. If only a + or − is present, it indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Counterion
160px, cation-exchange_resin.html" ;"title="Polystyrene sulfonate, a cation-exchange resin">Polystyrene sulfonate, a cation-exchange resin, is typically supplied with as the counterion. In chemistry, a counterion (sometimes written as "counter ion", pronounced as such) is the ion that accompanies an Ionic compound, ionic species in order to maintain Electric charge, electric neutrality. In table salt (NaCl, also known as sodium chloride) the sodium ion (positively charged) is the counterion for the chloride ion (negatively charged) and vice versa. A counterion will be more commonly referred to as an anion or a cation, depending on whether it is negatively or positively charged. Thus, the counterion to an anion will be a cation, and vice versa. In biochemistry, counterions are generally vaguely defined. Depending on their charge, proteins are associated with a variety of smaller anions and cations. In plant cells, the anion malate is often accumulated in the vacuole to decrea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weakly Coordinating Anion
Anions that interact weakly with cations are termed non-coordinating anions, although a more accurate term is weakly coordinating anion. Non-coordinating anions are useful in studying the reactivity of electrophilic cations. They are commonly found as counterions for cationic metal complexes with an unsaturated coordination sphere. These special anions are essential components of homogeneous alkene polymerisation catalysts, where the active catalyst is a coordinatively unsaturated, cationic transition metal complex. For example, they are employed as counterions for the 14 valence electron cations C5H5)2ZrRsup>+ (R = methyl or a growing polyethylene chain). Complexes derived from non-coordinating anions have been used to catalyze hydrogenation, hydrosilylation, oligomerization, and the living polymerization of alkenes. The popularization of non-coordinating anions has contributed to increased understanding of agostic complexes wherein hydrocarbons and hydrogen serve as ligand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedral Molecular Geometry
In a tetrahedral molecular geometry, a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. The bond angles are arccos(−) = 109.4712206...° ≈ 109.5° when all four substituents are the same, as in methane () as well as its heavier analogues. Methane and other perfectly symmetrical tetrahedral molecules belong to point group ''Td'', but most tetrahedral molecules have lower symmetry. Tetrahedral molecules can be chiral. Tetrahedral bond angle The bond angle for a symmetric tetrahedral molecule such as CH4 may be calculated using the dot product of two vectors. As shown in the diagram at left, the molecule can be inscribed in a cube with the tetravalent atom (e.g. carbon) at the cube centre which is the origin of coordinates, O. The four monovalent atoms (e.g. hydrogens) are at four corners of the cube (A, B, C, D) chosen so that no two atoms are at adjacent corners linked by only one cube edge. If the edge len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lucas' Reagent
"Lucas' reagent" is a solution of anhydrous zinc chloride in concentrated hydrochloric acid. This solution is used to classify alcohols of low molecular weight. The reaction is a substitution in which the chloride replaces a hydroxyl group. A positive test is indicated by a change from clear and colourless to turbid, signalling formation of a chloroalkane. Also, the best results for this test are observed in tertiary alcohols, as they form the respective alkyl halides fastest due to higher stability of the intermediate tertiary carbocation. The test was reported in 1930 and became a standard method in qualitative organic chemistry. The test has since become somewhat obsolete with the availability of various spectroscopic and chromatographic methods of analysis. It was named after Howard Lucas (1885–1963). Lucas test The Lucas test in alcohols is a test to differentiate between primary, secondary, and tertiary alcohols. It is based on the difference in reactivity of the th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloric Acid
Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is a component of the gastric acid in the digestive systems of most animal species, including humans. Hydrochloric acid is an important laboratory reagent and industrial chemical. Etymology Because it was produced from halite, rock salt according to the methods of Johann Rudolph Glauber, hydrochloric acid was historically called by European alchemists ''spirits of salt'' or ''acidum salis'' (salt acid). Both names are still used, especially in other languages, such as , , , , , , , , , , (''ensan''), zh, 盐酸 (''yánsuān''), and (''yeomsan''). Gaseous HCl was called ''marine acid air''. The name ''muriatic acid'' has the same origin (''muriatic'' means "pertaining to brine or salt", hence ''muriate'' means hydrochloride), and this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
