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Diphenylcarbazide
1,5-Diphenylcarbazide (or simply Diphenylcarbazide, often abbreviated DPC) is a chemical compound from the group of the carbazides. It has a structural formula similar to that of diphenylcarbazone and can be easily converted into it by oxidation. Properties Diphenylcarbazide is a white solid that is scarcely soluble in water, but readily soluble in organic solvents like acetone, hot ethanol and acetic acid. It forms colored complex compounds with certain metal ions. Diphenylcarbazide oxidizes to Diphenylcarbazone when exposed to light and air, turning pink in the process. Uses Diphenylcarbazide is used as a redox indicator and for the photometric determination of certain heavy metal ions, like those of Chromium, Mercury, Cadmium, Osmium, Rubidium, Technetium and more. Reacting a Diphenylcarbazide with Chromium (VI) compounds, such as chromates or dichromates produces diphenylcarbazone, which forms a red-violet complex with the chromium compounds. Chromium (III) compou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbazides
In chemistry, a carbazide is a functional group with the general formula RNH-NH(C=O)NH-NHR. They can be derived from the condensation reaction, condensation of carbonic acid with a hydrazine. Carbohydrazide is the simplest carbazide, with another common carbazide being diphenylcarbazide, which is used as an analytical reagent. Diphenylcarbazide forms an intense blue color with chromium in the hexavalent state. It has an Molar absorptivity, absorptivity coefficient of about 3400. That means very small amounts of chromium can be detected; 25 micrograms in 25 mL of solution are too dark to read on a spectral device, so concentrations well below that can be detected. Thiocarbazide The sulfur structural analog, analog is called a thiocarbazide, of which thiocarbohydrazide is the simplest example. Carbazone and thiocarbazone A carbazone is a partially oxidized carbazide with the general formula R=NNH(C=O)NH-NHR. The sulfur analog is called a thiocarbazone, of which dithizone is an ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphenylcarbazone
1,5-Diphenylcarbazone (or simply Diphenylcarbazone) is a chemical compound from the group of the carbazones (nitrogen compounds with the basic structure HN=N-CO-NH-NH2). Properties Diphenylcarbazone is an orange solid that dissolves well in Ethanol, Chloroform and Benzene and is almost insoluble in water. It forms a purple complex compound with Hg(II) ions. Likewise, other metal ions, such as Cr(III) ions form colored complexes with Diphenylcarbazone. Diphenylcarbazone can be produced from Diphenylcarbazide via oxidation. Certain commercial products of diphenylcarbazone are a mixture with Diphenylcarbazide, which also forms colored complex compounds with certain metal ions. Uses Diphenylcarbazone is used as an indicator for endpoint determination in mercurimetry: If a Sodium chloride solution is titrated with Mercury(II) nitrate solution, undissociated Mercury(II) chloride Mercury(II) chloride (or mercury bichloride, mercury dichloride), historically also known as sul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mol (unit)
The mole, symbol mol, is the unit of amount of substance in the International System of Units (SI). The quantity amount of substance is a measure of how many elementary entities of a given substance are in an object or sample. The mole is defined as containing exactly elementary entities. Depending on what the substance is, an elementary entity may be an atom, a molecule, an ion, an ion pair, or a subatomic particle such as an electron. For example, 10 moles of water (a chemical compound) and 10 moles of mercury (a chemical element), contain equal amounts of substance and the mercury contains exactly one atom for each molecule of the water, despite the two having different volumes and different masses. The number of elementary entities in one mole is known as the Avogadro number, which is the approximate number of nucleons (protons or neutrons) in one gram of ordinary matter. The previous definition of a mole was simply the number of elementary entities equal to that of 12 grams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium
Technetium is a chemical element with the symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive. All available technetium is produced as a synthetic element. Naturally occurring technetium is a spontaneous fission product in uranium ore and thorium ore, the most common source, or the product of neutron capture in molybdenum ores. This silvery gray, crystalline transition metal lies between manganese and rhenium in group 7 of the periodic table, and its chemical properties are intermediate between those of both adjacent elements. The most common naturally occurring isotope is 99Tc, in traces only. Many of technetium's properties had been predicted by Dmitri Mendeleev before it was discovered. Mendeleev noted a gap in his periodic table and gave the undiscovered element the provisional name '' ekamanganese'' (''Em''). In 1937, technetium (specifically the technetium-97 isotope) became the first predominantly artificial element to be produ ... [...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] |
Phenylhydrazine
Phenylhydrazine is the chemical compound with the formula . It is often abbreviated as . It is also found in edible mushrooms. Properties Phenylhydrazine forms monoclinic prisms that melt to an oil around room temperature which may turn yellow to dark red upon exposure to air. Phenylhydrazine is miscible with ethanol, diethyl ether, chloroform and benzene. It is sparingly soluble in water. Preparation Phenylhydrazine is prepared by oxidizing aniline with sodium nitrite in the presence of hydrogen chloride to form the diazonium salt, which is subsequently reduced using sodium sulfite in the presence of sodium hydroxide to form the final product.''Merck Index of Chemicals and Drugs, 9th ed.'' monograph 7098 History Phenylhydrazine was the first hydrazine derivative characterized, reported by Hermann Emil Fischer in 1875. He prepared it by reduction of a phenyl diazonium salt using sulfite salts. Fischer used phenylhydrazine to characterize sugars via formation of hydrazones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopropyl Alcohol
Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable organic compound with a pungent alcoholic odor. As an isopropyl group linked to a hydroxyl group (chemical formula ) it is the simplest example of a secondary alcohol, where the alcohol carbon atom is attached to two other carbon atoms. It is a structural isomer of propan-1-ol and ethyl methyl ether. It is used in the manufacture of a wide variety of industrial and household chemicals and is a common ingredient in products such as antiseptics, disinfectants, hand sanitizer and detergents. Well over one million tonnes is produced worldwide annually. Properties Isopropyl alcohol is miscible in water, ethanol, and chloroform as, like these compounds, isopropyl is a polar molecule. It dissolves ethyl cellulose, polyvinyl butyral, many oils, alkaloids, and natural resins. Unlike ethanol or methanol, isopropyl alcohol is not miscible with salt solutions and can be separ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Methoxyethanol
2-Methoxyethanol, or methyl cellosolve, is an organic compound with formula that is used mainly as a solvent. It is a clear, colorless liquid with an ether-like odor. It is in a class of solvents known as glycol ethers which are notable for their ability to dissolve a variety of different types of chemical compounds and for their miscibility with water and other solvents. It can be formed by the nucleophilic attack of methanol on protonated ethylene oxide followed by proton transfer: : + → + 2-Methoxyethanol is used as a solvent for many different purposes such as varnishes, dyes, and resins. It is also used as an additive in airplane deicing solutions. In organometallic chemistry it is commonly used for the synthesis of Vaska's complex and related compounds such as carbonylchlorohydridotris(triphenylphosphine)ruthenium (II). During these reactions the alcohol acts as a source of hydride and carbon monoxide. 2-Methoxyethanol is toxic to the bone marrow and testicles. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butanone
Butanone, also known as methyl ethyl ketone (MEK), is an organic compound with the formula CH3C(O)CH2CH3. This colourless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large scale, but occurs in nature only in trace amounts.Wilhelm Neier, Guenter Strehlke "2-Butanone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. It is partially soluble in water, and is commonly used as an industrial solvent. It is an isomer of another solvent, tetrahydrofuran. Production Butanone may be produced by oxidation of 2-butanol. The dehydrogenation of 2-butanol is catalysed by copper, zinc, or bronze: :CH3CH(OH)CH2CH3 → CH3C(O)CH2CH3 + H2 This is used to produce approximately 700 million kilograms yearly. Other syntheses that have been examined but not implemented include Wacker oxidation of 2-butene and oxidation of isobutylbenzene, which is analogous to the industrial production of acetone. The cumene process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Acetate
Ethyl acetate ( systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues, nail polish removers, and in the decaffeination process of tea and coffee. Ethyl acetate is the ester of ethanol and acetic acid; it is manufactured on a large scale for use as a solvent. Production and synthesis Ethyl acetate was first synthesized by the Count de Lauraguais in 1759 by distilling a mixture of ethanol and acetic acid. In 2004, an estimated 1.3 million tonnes were produced worldwide. The combined annual production in 1985 of Japan, North America, and Europe was about 400,000 tonnes. The global ethyl acetate market was valued at $3.3 billion in 2018. Ethyl acetate is synthesized in industry mainly via the classic Fischer esterification reaction of ethanol and acetic acid. This mixture converts to the ester in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parts-per Notation
In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they are pure numbers with no associated units of measurement. Commonly used are parts-per-million (ppm, ), parts-per-billion (ppb, ), parts-per-trillion (ppt, ) and parts-per-quadrillion (ppq, ). This notation is not part of the International System of Units (SI) system and its meaning is ambiguous. Overview Parts-per notation is often used describing dilute solutions in chemistry, for instance, the relative abundance of dissolved minerals or pollutants in water. The quantity "1 ppm" can be used for a mass fraction if a water-borne pollutant is present at one-millionth of a gram per gram of sample solution. When working with aqueous solutions, it is common to assume that the density of water is 1.00 g/mL. Therefore, it is common to equat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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