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PETN is practically insoluble in water (0.01 g/100 mL at 50 °C), weakly soluble in common nonpolar solvents such as aliphatic hydrocarbons (like gasoline) or tetrachloromethane, but soluble in some other organic solvents, particularly in acetone (about 15 g/100 g of the solution at 20 °C, 55 g/100 g at 60 °C) and dimethylformamide (40 g/100 ...
In particular, experiments on the diffusion of foreign material in a turbulent water stream, [6] vertical structure of water in lake bodies, [7] and lowest part of the atmosphere [8] found experimental evidence that eddy diffusion is indeed stronger than molecular diffusion and generally obeys the theory originally developed by G. I. Taylor ...
Pentane is an organic compound with the formula C 5 H 12 —that is, an alkane with five carbon atoms. The term may refer to any of three structural isomers, or to a mixture of them: in the IUPAC nomenclature, however, pentane means exclusively the n-pentane isomer, in which case pentanes refers to a mixture of them; the other two are called isopentane (methylbutane) and neopentane ...
Levinthal's paradox is a thought experiment in the field of computational protein structure prediction; protein folding seeks a stable energy configuration. An algorithmic search through all possible conformations to identify the minimum energy configuration (the native state) would take an immense duration; however in reality protein folding happens very quickly, even in the case of the most ...
Pentaerythritol was first reported in 1891 by German chemist Bernhard Tollens and his student P. Wigand. [5] It may be prepared via a base-catalyzed multiple-addition reaction between acetaldehyde and 3 equivalents of formaldehyde to give pentaerythrose (CAS: 3818-32-4), followed by a Cannizzaro reaction with a fourth equivalent of formaldehyde to give the final product plus formate ion.
The boiling point of 89.7 °C is 0.3 °C higher than the value of 89.4 °C predicted by Wiener's formula, based on the structure of the molecule and the boiling point of n-heptane. [2] [3] The speed of sound at 3 MHz is 1149.5 m/s at 20 °C and 889.5 m/s at 80 °C. [7] [8] [9]
where μ is the electric dipole moment of the effectively polarized water molecule (2.35 D for the SPC/E model), μ 0 is the dipole moment of an isolated water molecule (1.85 D from experiment), and α i is an isotropic polarizability constant, with a value of 1.608 × 10 −40 F·m 2. Since the charges in the model are constant, this ...
The number of electron pairs in the valence shell of a central atom is determined after drawing the Lewis structure of the molecule, and expanding it to show all bonding groups and lone pairs of electrons. [1]: 410–417 In VSEPR theory, a double bond or triple bond is treated as a single bonding group. [1]