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  2. 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.

  3. Chaotropic agent - Wikipedia

    en.wikipedia.org/wiki/Chaotropic_agent

    A chaotropic agent is a molecule in water solution that can disrupt the hydrogen bonding network between water molecules (i.e. exerts chaotropic activity).This has an effect on the stability of the native state of other molecules in the solution, mainly macromolecules (proteins, nucleic acids) by weakening the hydrophobic effect.

  4. Hexafluoro-2-propanol - Wikipedia

    en.wikipedia.org/wiki/Hexafluoro-2-propanol

    As a solvent, hexafluoro-2-propanol is polar and exhibits strong hydrogen bonding properties. Testament to the strength of its hydrogen-bonding tendency is the fact that its 1:1 complex with THF distills near 100 °C. It has a relatively high dielectric constant of 16.7. It is also relatively acidic, with a pKa of 9.3, comparable to that for ...

  5. Hydrophobicity scales - Wikipedia

    en.wikipedia.org/wiki/Hydrophobicity_scales

    The effect originates from the disruption of highly dynamic hydrogen bonds between molecules of liquid water. Polar chemical groups, such as OH group in methanol do not cause the hydrophobic effect. However, a pure hydrocarbon molecule, for example hexane, cannot accept or donate hydrogen bonds to water. Introduction of hexane into water causes ...

  6. Solvent effects - Wikipedia

    en.wikipedia.org/wiki/Solvent_effects

    Note the decrease in ΔG ‡ activation for the polar-solvent reaction conditions. This arises from the fact that polar solvents stabilize the formation of the carbocation intermediate to a greater extent than the non-polar-solvent conditions. This is apparent in the ΔE a, ΔΔG ‡ activation. On the right is an S N 2 reaction coordinate diagram.

  7. Chemical bonding of water - Wikipedia

    en.wikipedia.org/wiki/Chemical_bonding_of_water

    2 O) is a simple triatomic bent molecule with C 2v molecular symmetry and bond angle of 104.5° between the central oxygen atom and the hydrogen atoms. Despite being one of the simplest triatomic molecules , its chemical bonding scheme is nonetheless complex as many of its bonding properties such as bond angle , ionization energy , and ...

  8. Polar surface area - Wikipedia

    en.wikipedia.org/wiki/Polar_surface_area

    The polar surface area (PSA) or topological polar surface area (TPSA) of a molecule is defined as the surface sum over all polar atoms or molecules, primarily oxygen and nitrogen, also including their attached hydrogen atoms. PSA is a commonly used medicinal chemistry metric for the

  9. Regenerative fuel cell - Wikipedia

    en.wikipedia.org/wiki/Regenerative_fuel_cell

    In this reverse mode, the polarity of the cell is opposite to that for the fuel cell mode. The following reactions describe the chemical process in the hydrogen generation mode: At the anode (where water is oxidized): H 2 O→1/2O 2 + 2H + + 2e −. At the cathode (where hydrogen is produced): 2H + + 2e − → H 2