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List Of Cooling Baths
This article contains a list of cooling bath mixtures. Table References * * * {{Cite journal , last1 = Rondeau , first1 = Roger E. , year = 1966 , title = Slush baths , journal = Journal of Chemical & Engineering Data , volume = 11 , pages = 124 , doi = 10.1021/je60028a037 , postscript = Cooling Cooling is removal of heat, usually resulting in a lower temperature and/or phase change. Temperature lowering achieved by any other means may also be called cooling.ASHRAE Terminology, https://www.ashrae.org/technical-resources/free-resources/as ... baths Baths ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooling Bath
A cooling bath or ice bath, in laboratory chemistry practice, is a liquid mixture which is used to maintain low temperatures, typically between 13 °C and −196 °C. These low temperatures are used to collect liquids after distillation, to remove solvents using a rotary evaporator, or to perform a chemical reaction below room temperature (see Kinetic control). Cooling baths are generally one of two types: (a) a cold fluid (particularly liquid nitrogen, water, or even air) — but most commonly the term refers to (b) a mixture of 3 components: (1) a cooling agent (such as dry ice or ice); (2) a liquid "carrier" (such as liquid water, ethylene glycol, acetone, etc.), which transfers heat between the bath and the vessel; (3) an additive to depress the melting point of the solid/liquid system. A familiar example of this is the use of an ice/rock-salt mixture to freeze ice cream. Adding salt lowers the freezing temperature of water, lowering the minimum temperature attaina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Chloride
Sodium chloride , commonly known as salt (although sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g/mol respectively, 100 g of NaCl contains 39.34 g Na and 60.66 g Cl. Sodium chloride is the salt most responsible for the salinity of seawater and of the extracellular fluid of many multicellular organisms. In its edible form, salt (also known as ''table salt'') is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. Another major application of sodium chloride is de-icing of roadways in sub-freezing weather. Uses In addition to the familiar domestic uses of salt, more dominant applications of the approximately 250 million tonnes per year production (2008 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octane
Octane is a hydrocarbon and an alkane with the chemical formula , and the condensed structural formula . Octane has many structural isomers that differ by the amount and location of branching in the carbon chain. One of these isomers, 2,2,4-Trimethylpentane, 2,2,4-trimethylpentane (commonly called iso-octane) is used as one of the standard values in the octane rating scale. Octane is a component of gasoline (petrol). As with all low-molecular-weight hydrocarbons, octane is volatility (chemistry), volatile and very flammable. Use of the term in gasoline "Octane" is colloquially used as a short form of "octane rating," particularly in the expression "high octane". "Octane rating" is an index of a fuel's ability to resist engine knock in engines having different compression ratios, which is a characteristic of octane's branched-chain isomers, especially iso-octane. The octane rating of gasoline is not directly related to the power output of an engine. Using gasoline of a higher o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-Xylene
''m''-Xylene ( ''meta''-xylene) is an aromatic hydrocarbon. It is one of the three isomers of dimethylbenzene known collectively as xylenes. The ''m-'' stands for ''meta-'', indicating that the two methyl groups in ''m''-xylene occupy positions 1 and 3 on a benzene ring. It is in the positions of the two methyl groups, their arene substitution pattern, that it differs from the other isomers, ''o''-xylene and ''p''-xylene. All have the same chemical formula C6H4(CH3)2. All xylene isomers are colorless and highly flammable. Production and use Petroleum contains about 1 weight percent xylenes. The ''meta'' isomer can be isolated from a mix of xylenes by the partial sulfonation (to which other isomers are less prone) followed by removal of unsulfonated oils and steam distillation of the sulfonated product. The major use of ''meta''-xylene is in the production of isophthalic acid, which is used as a copolymerizing monomer to alter the properties of polyethylene terephthalate. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexanone
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has an odor reminiscent of acetone. Over time, samples of cyclohexanone assume a pale yellow color. Cyclohexanone is slightly soluble in water and miscible with common organic solvents. Billions of kilograms are produced annually, mainly as a precursor to nylon. Production Cyclohexanone is produced by the oxidation of cyclohexane in air, typically using cobalt catalysts: :C6H12 + O2 → (CH2)5CO + H2O This process forms cyclohexanol as a by-product, and this mixture, called "KA Oil" for ketone-alcohol oil, is the main feedstock for the production of adipic acid. The oxidation involves radicals and the hydroperoxide C6H11O2H as an intermediate. In some cases, purified cyclohexanol, obtained by hydration of cyclohexene, is the precursor. Alternatively, cyclohexanone can be produced by the partial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom. It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. Pyridine is colorless, but older or impure samples can appear yellow, due to the formation of extended, unsaturated polymeric chains, which show significant electrical conductivity. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. As of 2016, it is synthesized on the scale of about 20,000 tons per year worldwide. Properties Physical properties The molecular electric dipole moment is 2.2 debyes. Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1. The standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetonitrile
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic). It is produced mainly as a byproduct of acrylonitrile manufacture. It is used as a polar aprotic solvent in organic synthesis and in the purification of butadiene. The skeleton is linear with a short distance of 1.16 Å. Acetonitrile was first prepared in 1847 by the French chemist Jean-Baptiste Dumas. Applications Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower. Heat is then employed in the separatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-Heptanone
3-Heptanone (butyl ethyl ketone), is a seven carbon ketone. It is a colorless liquid with a "green odor," also described to have a fruity scent. It is often used as a perfume/fragrance, as a solvent for cellulose, nitrocellulose, or vinyl resins, and as a synthetic building block in the preparation of other organic molecules. Preparation 3-Heptanone is produced industrially through reductive condensation of propionaldehyde (propanal) with butanone (methyl ethyl ketone). This reaction yields hept-4-en-3-one, which is subsequently hydrogenated Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ... to 3-heptanone. : + → + : + → References {{DEFAULTSORT:Heptanone, 3- Heptanones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-Toluidine
There are three isomers of toluidine, which are organic compounds. These isomers are ''o''-toluidine, ''m''-toluidine, and ''p''-toluidine, with the prefixed letter abbreviating, respectively, ''ortho''; ''meta''; and ''para''. All three are aryl amines whose chemical structures are similar to aniline except that a methyl group is substituted onto the benzene ring. The difference between these three isomers is the position where the methyl group (–CH3) is bonded to the ring relative to the amino functional group (–NH2); see illustration of the chemical structures below. The chemical properties of the toluidines are quite similar to those of aniline, and toluidines have properties in common with other aromatic amines. Due to the amino group bonded to the aromatic ring, the toluidines are weakly basic. The toluidines are poorly soluble in pure water but dissolve well in acidic water due to formation of ammonium salts, as usual for organic amines. ''ortho''- and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromobenzene
Bromobenzene is an aryl halide, C6H5Br. It is a colourless liquid although older samples can appear yellow. It is a reagent in organic synthesis. Synthesis and reactions Bromobenzene is prepared by the action of bromine on benzene in the presence of Lewis acid catalysts such as aluminium chloride or ferric bromide. Bromobenzene is used to introduce a phenyl group into other compounds. One method involves its conversion to the Grignard reagent, phenylmagnesium bromide. This reagent can be used, e.g. in the reaction with carbon dioxide to prepare benzoic acid. Other methods involve palladium-catalyzed coupling reactions, such as the Suzuki reaction. Bromobenzene is used as a precursor in the manufacture of phencyclidine. Toxicity Animal tests indicate low toxicity. Little is known about chronic effects. For liver toxicity, the 3,4-epoxide are proposed intermediates. See also *Fluorobenzene *Chlorobenzene *Iodobenzene Iodobenzene is an organoiodine compound consisting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
