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Methanesulfonyl Azide
Methanesulfonyl azide is the azide of methanesulfonic acid. It is used as a reagent for the production of diazo compounds. Preparation Methanesulfonyl azide can be prepared from methanesulfonyl chloride by reaction with sodium azide in ethanol or methanol, Preparation ''in situ'' is also possible, for example in acetonitrile, and is advantageous to avoid explosion hazards. Properties Methanesulfonyl azide melts at 18 °C and decomposes from 120 °C. Like many other azides, it is explosive. At low temperature, methanesulfonyl azide crystallizes in the triclinic crystal system in the space group ''P''1 with the lattice parameters ''a'' = 5.6240 Å; ''b'' = 5.9498 Å, ''c'' = 7.6329 Å, ''α'' = 72.216°, ''β'' = 70.897°, and ''γ'' = 88.601°, and two molecules per unit cell. Mesyl azide is an antidote for hydrogen sulfide poisoning in mice. Reactions Methanesulfonyl azide is part of the sulfonyl azides, a family of reagents for diazo transfer. Within the fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mole (unit)
The mole (symbol mol) is a unit of measurement, the base unit in the International System of Units (SI) for ''amount of substance'', an SI base quantity proportional to the number of elementary entities of a substance. One mole is an aggregate of exactly elementary entities (approximately 602 sextillion or 602 billion times a trillion), which can be atoms, molecules, ions, ion pairs, or other particles. The number of particles in a mole is the Avogadro number (symbol ) and the numerical value of the '' Avogadro constant'' (symbol ) expressed in mol−1. The relationship between the mole, Avogadro number, and Avogadro constant can be expressed in the following equation:1\text = \frac = \frac The current SI value of the mole is based on the historical definition of the mole as the amount of substance that corresponds to the number of atoms in 12 grams of 12C, which made the molar mass of a compound in grams per mole, numerically equal to the average molecular mass or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unit Cell
In geometry, biology, mineralogy and solid state physics, a unit cell is a repeating unit formed by the vectors spanning the points of a lattice. Despite its suggestive name, the unit cell (unlike a unit vector In mathematics, a unit vector in a normed vector space is a Vector (mathematics and physics), vector (often a vector (geometry), spatial vector) of Norm (mathematics), length 1. A unit vector is often denoted by a lowercase letter with a circumfle ..., for example) does not necessarily have unit size, or even a particular size at all. Rather, the primitive cell is the closest analogy to a unit vector, since it has a determined size for a given lattice and is the basic building block from which larger cells are constructed. The concept is used particularly in describing crystal structure in two and three dimensions, though it makes sense in all dimensions. A lattice can be characterized by the geometry of its unit cell, which is a section of the tiling (a parallelogra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Compounds
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bonded to the rest of the molecule by a single covalent bond (), it can be found on its own in any of three forms: methanide anion (), methylium cation () or methyl radical (). The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed. Methyl cation, anion, and radical Methyl cation The methylium cation () exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of the cation, and this simplification is used pervasively in organic chemistry. For exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually faint, and may be similar to that of gasoline or Naphtha, lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to naturally occurring petroleum, natural gas and coal, or their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrene
In chemistry, a nitrene or imene () is the nitrogen analogue of a carbene. The nitrogen atom is uncharged and valence (chemistry)#monovalent, monovalent, so it has only 6 electrons in its valence level—two covalent bonded and four non-bonded electrons. It is therefore considered an electrophile due to the octet rule, unsatisfied octet. A nitrene is a reactive intermediate and is involved in many chemical reactions. The simplest nitrene, HN, is called imidogen, and that term is sometimes used as a synonym for the nitrene class. Electron configuration In the simplest case, the linear N–H molecule (imidogen) has its nitrogen atom sp hybrid orbital, sp hybridized, with two of its four non-bonded electrons as a lone pair in an sp orbital and the other two occupying a degenerate orbital, degenerate pair of p orbitals. The electron configuration is consistent with Hund's rule: the low energy form is a triplet state, triplet with one electron in each of the p orbitals and the high en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neon
Neon is a chemical element; it has symbol Ne and atomic number 10. It is the second noble gas in the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with approximately two-thirds the density of air. Neon was discovered in 1898 alongside krypton and xenon, identified as one of the three remaining rare inert elements in dry air after the removal of nitrogen, oxygen, argon, and carbon dioxide. Its discovery was marked by the distinctive bright red emission spectrum it exhibited, leading to its immediate recognition as a new element. The name ''neon'' originates from the Greek word , a neuter singular form of (), meaning 'new'. Neon is a chemically inert gas; although neon compounds do exist, they are primarily ionic molecules or fragile molecules held together by van der Waals forces. The synthesis of most neon in the cosmos resulted from the nuclear fusion within stars of oxygen and helium through the alpha-capture proce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argon
Argon is a chemical element; it has symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abundant as water vapor (which averages about 4000 ppmv, but varies greatly), 23 times as abundant as carbon dioxide (400 ppmv), and more than 500 times as abundant as neon (18 ppmv). Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in supernovas. The name "argon" is derived from the Greek word , neuter singular form of meaning 'lazy' or 'inactive', as a reference to the fact that the element undergoes almost no chemical reactions. The complete oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrix (chemical Analysis)
In chemical analysis, matrix refers to the components of a sample other than the analyte of interest. The matrix can have a considerable effect on the way the analysis is conducted and the quality of the results are obtained; such effects are called matrix effects.F. W. Fifield, P. J. Haines. ''Environmental Analytical Chemistry''. Blackwell Publishing, 2000, p. 4-5. . For example, the ionic strength of the solution can have an effect on the activity coefficients of the analytes.Harris, D. C. ''Quantitative Chemical Analysis'', 4th ed. Freeman, 1995, pp.194, 404. . The most common approach for accounting for matrix effects is to build a calibration curve using standard samples with known analyte concentration and which try to approximate the matrix of the sample as much as possible. This is especially important for solid samples where there is a strong matrix influence.Marco Aurelio Zezzi Arruda. ''Trends in Sample Preparation''. Nova Publishers, 2006, p. 15-18. . In cases with comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photolysis
Photodissociation, photolysis, photodecomposition, or photofragmentation is a chemical reaction in which molecules of a chemical compound are broken down by absorption of light or photons. It is defined as the interaction of one or more photons with one target molecule that dissociates into two fragments. Here, “light” is broadly defined as radiation spanning the vacuum ultraviolet (VUV), ultraviolet (UV), visible, and infrared (IR) regions of the electromagnetic spectrum. To break covalent bonds, photon energies corresponding to visible, UV, or VUV light are typically required, whereas IR photons may be sufficiently energetic to detach ligands from coordination complexes or to fragment supramolecular complexes. Photolysis in photosynthesis Photolysis is part of the light-dependent reaction, light phase, photochemical phase, or Hill reaction of photosynthesis. The general reaction of photosynthetic photolysis can be given in terms of photons as: :\ce + 2 \text \longri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazo Transfer
In organic chemistry, the diazo group is an organic moiety consisting of two linked nitrogen atoms at the terminal position. Overall charge-neutral organic compounds containing the diazo group bound to a carbon atom are called diazo compounds or diazoalkanes and are described by the general structural formula . The simplest example of a diazo compound is diazomethane, . Diazo compounds () should not be confused with azo compounds () or with diazonium compounds (). Structure The electronic structure of diazo compounds is characterized by π electron density delocalized over the α-carbon and two nitrogen atoms, along with an orthogonal π system with electron density delocalized over only the terminal nitrogen atoms. Because all octet rule-satisfying resonance forms of diazo compounds have formal charges, they are members of a class of compounds known as 1,3-dipoles. Some of the most stable diazo compounds are α-diazo-β-diketones and α-diazo-β-diesters, in which the ele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfonyl Azide
In organosulfur chemistry, a sulfonyl group is either a functional group found primarily in sulfones, or a substituent obtained from a sulfonic acid by the removal of the hydroxyl group, similarly to acyl groups. Group Sulfonyl groups can be written as having the general formula , where there are two double bonds between the sulfur and oxygen. Sulfonyl groups can be reduced to the sulfide with diisobutylaluminium hydride (DIBALH). Lithium aluminium hydride () reduces some but not all sulfones to sulfides. In inorganic chemistry, when the group is not connected to any carbon atoms, it is referred to as sulfuryl. Examples of sulfonyl group substituents The names of sulfonyl groups typically end in -syl, such as: : See also * Sulfonyl halide * Sulfonamide * Sulfonate * Methylsulfonylmethane Dimethyl sulfone (DMSO2) is an organosulfur compound with the formula . It is also known by several other names including methyl sulfone and (especially in alternative medicine) methylsul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laboratory Mice
The laboratory mouse or lab mouse is a small mammal of the order Rodentia which is bred and used for scientific research or feeders for certain pets. Laboratory animal sources for these mice are usually of the species ''Mus musculus''. They are the most commonly used mammalian research model and are used for research in genetics, physiology, psychology, medicine and other scientific disciplines. Mice belong to the Euarchontoglires clade, which includes humans. This close relationship, the associated high homology with humans, their ease of maintenance and handling, and their high reproduction rate, make mice particularly suitable models for human-oriented research. The laboratory mouse genome has been sequenced and many mouse genes have human homologues. Lab mice are sold at pet stores for snake food and can also be kept as pets. Other mouse species sometimes used in laboratory research include two American species, the white-footed mouse (''Peromyscus leucopus'') and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
