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Chlorine Tetroxide
Chlorine tetroxide is an unstable chlorine oxide with the chemical formula . History Gomberg's mistaken 1923 production In 1923, the famous radical chemist Moses Gomberg proposed a production method of chlorine tetroxide. He claimed that treating iodine and silver perchlorate in anhydrous diethyl ether produced it. :I2 + 2 AgClO4 → 2 AgI + (ClO4)2 However, later researchers claimed that the product was iodine perchlorate. So far, however, there is no certain evidence for the existence of iodine perchlorate either. Eachus' 1968 production In 1968, Eachus synthesized it by exposing potassium chlorate to gamma rays at 77 K. It is a reaction intermediate of the decomposition of dichlorine heptoxide. Properties The electron affinity energy of chlorine tetroxide can be figured out using the Born–Haber cycle and the lattice energy data of perchlorates. It is about 561 kJ/mol. The structure of chlorine tetroxide is uncertain; the molecular point group Molecular symmetry i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorine Oxide
Chlorine and oxygen can bond in many ways: * chlorine monoxide, , chlorine (II) oxide * chlorine peroxide, , dimer of chlorine (II) oxide *chlorine dioxide, , chlorine (IV) oxide * chloroperoxyl, *chlorine trioxide, ClO3, chlorine (VI) oxide *dichlorine monoxide, Cl2O, chlorine (I) oxide *Three dichlorine dioxides: **ClO dimer, Cl2O2, chlorine (I) peroxide **chloryl chloride, ClO2Cl, chlorine (0,IV) oxide ** chlorine chlorite, ClOClO, chlorine (I,III) oxide * dichlorine trioxide, Cl2O3, chlorine (I,V) oxide *dichlorine tetroxide, also known as chlorine perchlorate, ClOClO3, chlorine (I,VII) oxide *dichlorine pentoxide, Cl2O5, is hypothetical *dichlorine hexoxide, chloryl perchlorate, Cl2O6, chlorine (V,VII) oxide *dichlorine heptoxide, Cl2O7, chlorine (VII) oxide *chlorine tetroxide, * chlorine (VII) oxide peroxide, (OClO3)2 Several ions are also chlorine oxides: *chloryl, * perchloryl, * hypochlorite, ClO− * chlorite, ClO2− * chlorate, ClO3− *perchlorate, ClO4− See a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Formula
In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include Subscript and superscript, subscripts and superscripts. A chemical formula is not a chemical nomenclature, chemical name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called ''empirical formulae'', which use letters and numbers ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moses Gomberg
Moses Gomberg (February 8, 1866 – February 12, 1947) was a chemistry professor at the University of Michigan. He was elected to the National Academy of Sciences and served as president of the American Chemical Society. Early life and education He was born in Yelisavetgrad, Russian Empire to a Jewish merchant family. His father was Hershko (Hirsh) Gomberg and his mother was Maryam-Ethel Reznikova. In 1884, the family emigrated to Chicago to escape the pogroms following the assassination of Czar Alexander II. In Chicago he worked at the Stock Yards while attending Lake High School. In 1886, Moses entered the University of Michigan, where he obtained his B.Sc. in 1890 and his doctorate in 1894 under the supervision of A. B. Prescott. His thesis, titled "''Trimethylxanthine and Some of its Derivatives''", dealt with the derivatization of caffeine. Career Appointed an instructor in 1893, Gomberg worked at the University of Michigan for the duration of his professional academic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek 'violet-coloured'. Iodine occurs in many oxidation states, including iodide (I−), iodate (), and the various periodate anions. It is the least abundant of the stable halogens, being the sixty-first most abundant element. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic compound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Perchlorate
Silver perchlorate is the chemical compound with the formula AgClO4. This white solid forms a monohydrate and is mildly deliquescent. It is a useful source of the Ag+ ion, although the presence of perchlorate presents risks. It is used as a catalyst in organic chemistry. Production Silver perchlorate is created by heating a mixture of perchloric acid with silver nitrate. Alternatively, it can be prepared by the reaction between barium perchlorate and silver sulfate, or from the reaction of perchloric acid with silver oxide. Solubility Silver perchlorate is noteworthy for its solubility in aromatic solvents such as benzene (52.8 g/L) and toluene (1010 g/L). In these solvents, the silver cation binds to the arene, as has been demonstrated by extensive crystallographic studies on crystals obtained from such solutions. Its solubility in water is extremely high, up to 500 g per 100 mL water. Related reagents Similar to silver nitrate, silver perchlorate is an effective reagent fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It has been used as a recreational drug to cause intoxication. Production Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Ethanol is mixed with a stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine Perchlorate
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek 'violet-coloured'. Iodine occurs in many oxidation states, including iodide (I−), iodate (), and the various periodate anions. It is the least abundant of the stable halogens, being the sixty-first most abundant element. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Chlorate
Potassium chlorate is a compound containing potassium, chlorine and oxygen, with the molecular formula KClO3. In its pure form, it is a white crystalline substance. After sodium chlorate, it is the second most common chlorate in industrial use. It is a strong oxidizing agent and its most important application is in safety matches. In other applications it is mostly obsolete and has been replaced by safer alternatives in recent decades. It has been used * in fireworks, propellants and explosives, * to prepare oxygen, both in the lab and in chemical oxygen generators, * as a disinfectant, for example in medical mouthwashes, * in agriculture as an herbicide. Production On the industrial scale, potassium chlorate is produced by the salt metathesis reaction of sodium chlorate and potassium chloride: : NaClO3 + KCl → NaCl + KClO3 The reaction is driven by the low solubility of potassium chlorate in water. The equilibrium of the reaction is shifted to the right hand side by the continuo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Intermediate
In chemistry, a reaction intermediate or an intermediate is a molecular entity that is formed from the reactants (or preceding intermediates) but is consumed in further reactions in stepwise chemical reactions that contain multiple elementary steps. Intermediates are the reaction product of one elementary step, but do not appear in the chemical equation for an overall chemical equation. For example, consider this hypothetical stepwise reaction: :A + B -> C + D The reaction includes two elementary steps: :A + B -> X :X -> C + D In this example, X is a reaction intermediate. IUPAC definition The IUPAC Gold Book defines an ''intermediate'' as a compound that has a lifetime greater than a molecular vibration that is formed (directly or indirectly) from the reactants and reacts further to give (either directly or indirectly) the products of a chemical reaction. The lifetime condition distinguishes true, chemically distinct intermediates from vibrational states or such transition st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichlorine Heptoxide
Dichlorine heptoxide is the chemical compound with the formula Cl2O7. This chlorine oxide is the anhydride of perchloric acid. It is produced by the careful distillation of perchloric acid in the presence of the dehydrating agent phosphorus pentoxide: :2 HClO4 + P4O10 → Cl2O7 + H2P4O11 The chlorine(VII) oxide can be distilled off from the mixture. It may also be formed by illumination on mixtures of chlorine and ozone. It slowly hydrolyzes back to perchloric acid. Structure Cl2O7 is an endergonic molecule, meaning it is intrinsically unstable, decomposing to its constituent elements with release of energy: :2 Cl2O7 → 2 Cl2 + 7 O2 (Δ''H°'' = –132 kcal/mol) Cl2O7 is bent with Cl−O−Cl angle of 118.6° giving the molecule C2 symmetry. The terminal Cl−O distances are 1.709 Å and the Cl=O distances are 1.405 Å. In this compound, chlorine exists in its highest formal oxidation state of +7, although the bonding in this molecule is significantly c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Affinity
The electron affinity (''E''ea) of an atom or molecule is defined as the amount of energy released when an electron attaches to a neutral atom or molecule in the gaseous state to form an anion. ::X(g) + e− → X−(g) + energy Note that this is not the same as the enthalpy change of electron capture ionization, which is defined as negative when energy is released. In other words, the enthalpy change and the electron affinity differ by a negative sign. In solid state physics, the electron affinity for a surface is defined somewhat differently ( see below). Measurement and use of electron affinity This property is used to measure atoms and molecules in the gaseous state only, since in a solid or liquid state their energy levels would be changed by contact with other atoms or molecules. A list of the electron affinities was used by Robert S. Mulliken to develop an electronegativity scale for atoms, equal to the average of the electrons affinity and ionization potential. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Born–Haber Cycle
The Born–Haber cycle is an approach to analyze reaction energies. It was named after the two German scientists Max Born and Fritz Haber, who developed it in 1919. It was also independently formulated by Kasimir Fajans and published concurrently in the same issue of the same journal. The cycle is concerned with the formation of an ionic compound from the reaction of a metal (often a Group I or Group II element) with a halogen or other non-metallic element such as oxygen. Born–Haber cycles are used primarily as a means of calculating lattice energy (or more precisely enthalpyThe difference between energy and enthalpy is very small and the two terms are interchanged freely in this article.), which cannot otherwise be measured directly. The lattice enthalpy is the enthalpy change involved in the formation of an ionic compound from gaseous ions (an exothermic process), or sometimes defined as the energy to break the ionic compound into gaseous ions (an endothermic process). A Born ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
