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This Wikipedia page provides a comprehensive list of boiling and freezing points for various solvents.
Water, being the most polar-solvent listed above, stabilizes the ionized species to a greater extent than does DMSO or Acetonitrile. Ionization - and, thus, acidity - would be greatest in water and lesser in DMSO and Acetonitrile, as seen in the table below, which shows p K a values at 25 °C for acetonitrile (ACN) [ 2 ] [ 3 ] [ 4 ] and ...
log 10 of Acetonitrile vapor pressure. ... Vapor-liquid Equilibrium for Acetonitrile/Methanol [4] P = 760 mmHg BP Temp. °C % by mole methanol liquid vapor 79.20: 2.5:
In reversed phase chromatography, the most polar compounds elute first with the more nonpolar compounds eluting later. The mobile phase is generally a mixture of water and miscible polarity-modifying organic solvent, such as methanol, acetonitrile or THF. Retention increases as the fraction of the polar solvent (water) in the mobile phase is ...
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula CH 3 CN and structure H 3 C−C≡N. This colourless liquid is the simplest organic nitrile ( hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic ).
Isopropanol (2-propanol) can also be used, because of its strong eluting properties, but its use is limited by its high viscosity, which results in higher backpressures. Both acetonitrile and methanol are less viscous than isopropanol, although a mixture of 50:50 percent of methanol:water is also very viscous and causes high backpressures.
A polar aprotic solvent is a solvent that lacks an acidic proton and is polar. Such solvents lack hydroxyl and amine groups. In contrast to protic solvents, these solvents do not serve as proton donors in hydrogen bonding, although they can be proton acceptors. Many solvents, including chlorocarbons and hydrocarbons, are classifiable as aprotic ...
Polar molecules must contain one or more polar bonds due to a difference in electronegativity between the bonded atoms. Molecules containing polar bonds have no molecular polarity if the bond dipoles cancel each other out by symmetry. Polar molecules interact through dipole-dipole intermolecular forces and hydrogen bonds.