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  2. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    DMSO is widely used as an alternative to water because it has a lower dielectric constant than water, and is less polar and so dissolves non-polar, hydrophobic substances more easily. It has a measurable pK a range of about 1 to 30. Acetonitrile is less basic than DMSO, and, so, in general, acids are weaker and bases are stronger in this solvent.

  3. Z-matrix (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Z-matrix_(chemistry)

    In chemistry, the Z-matrix is a way to represent a system built of atoms.A Z-matrix is also known as an internal coordinate representation.It provides a description of each atom in a molecule in terms of its atomic number, bond length, bond angle, and dihedral angle, the so-called internal coordinates, [1] [2] although it is not always the case that a Z-matrix will give information regarding ...

  4. Oxygen compounds - Wikipedia

    en.wikipedia.org/wiki/Oxygen_compounds

    Its bulk properties partly result from the interaction of its component atoms, oxygen and hydrogen, with atoms of nearby water molecules. Hydrogen atoms are covalently bonded to oxygen in a water molecule but also have an additional attraction (about 23.3 kJ·mol −1 per hydrogen atom) to an adjacent oxygen atom in a separate molecule. [2]

  5. Ortho effect - Wikipedia

    en.wikipedia.org/wiki/Ortho_effect

    Ortho effect is an organic chemistry phenomenon where the presence of a chemical group at the at ortho position or the 1 and 2 position of a phenyl ring, relative to the carboxylic compound changes the chemical properties of the compound.

  6. Polar surface area - Wikipedia

    en.wikipedia.org/wiki/Polar_surface_area

    Molecules with a polar surface area of greater than 140 angstroms squared (Å 2) tend to be poor at permeating cell membranes. [1] For molecules to penetrate the blood–brain barrier (and thus act on receptors in the central nervous system), a PSA less than 90 Å 2 is usually needed. [2] TPSA is a valuable tool in drug discovery and development.

  7. Amine oxide - Wikipedia

    en.wikipedia.org/wiki/Amine_oxide

    In chemistry, an amine oxide, also known as an amine N-oxide or simply N-oxide, is a chemical compound that has the chemical formula R 3 N + −O −. It contains a nitrogen - oxygen coordinate covalent bond with three additional hydrogen and/or substituent -groups attached to nitrogen.

  8. Chemical polarity - Wikipedia

    en.wikipedia.org/wiki/Chemical_polarity

    In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar bonds due to a difference in electronegativity between the bonded atoms.

  9. Metal ions in aqueous solution - Wikipedia

    en.wikipedia.org/wiki/Metal_ions_in_aqueous_solution

    A metal ion in aqueous solution or aqua ion is a cation, dissolved in water, of chemical formula [M(H 2 O) n] z+.The solvation number, n, determined by a variety of experimental methods is 4 for Li + and Be 2+ and 6 for most elements in periods 3 and 4 of the periodic table.