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  2. HSAB theory - Wikipedia

    en.wikipedia.org/wiki/HSAB_theory

    The E and C parameters refer, respectively, to the electrostatic and covalent contributions to the strength of the bonds that the acid and base will form. The equation is -ΔH = E A E B + C A C B + W. The W term represents a constant energy contribution for acidbase reaction such as the cleavage of a dimeric acid or base. The equation ...

  3. History of chemistry - Wikipedia

    en.wikipedia.org/wiki/History_of_chemistry

    For cases where no sharing was involved, Lewis in 1923 developed the electron pair theory of acids and base: Lewis redefined an acid as any atom or molecule with an incomplete octet that was thus capable of accepting electrons from another atom; bases were, of course, electron donors. His theory is known as the concept of Lewis acids and bases.

  4. Brønsted–Lowry acid–base theory - Wikipedia

    en.wikipedia.org/wiki/Brønsted–Lowry_acid...

    The Brønsted–Lowry theory (also called proton theory of acids and bases [1]) is an acidbase reaction theory which was first developed by Johannes Nicolaus Brønsted and Thomas Martin Lowry independently in 1923.

  5. Leveling effect - Wikipedia

    en.wikipedia.org/wiki/Leveling_effect

    Strong bases are leveling solvents for acids, weak bases are differentiating solvents for acids. In a leveling solvent, many acids are completely dissociated and are thus of the same strength. All acids tend to become indistinguishable in strength when dissolved in strongly basic solvents owing to the greater affinity of strong bases for protons.

  6. Acid–base titration - Wikipedia

    en.wikipedia.org/wiki/Acidbase_titration

    acid + base → salt + water. For example: HCl + NaOH → NaCl + H 2 O. Acidimetry is the specialized analytical use of acid-base titration to determine the concentration of a basic (alkaline) substance using standard acid. This can be used for weak bases and strong bases. [8] An example of an acidimetric titration involving a strong base is as ...

  7. Chemical substance - Wikipedia

    en.wikipedia.org/wiki/Chemical_substance

    Colors of a single chemical in different solvents, under visible and UV light, showing how the chemical interacts dynamically with its solvent environmentIn addition to the generic definition offered above, there are several niche fields where the term "chemical substance" may take alternate usages that are widely accepted, some of which are outlined in the sections below.

  8. Chirality (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Chirality_(chemistry)

    Two enantiomers of a generic amino acid that are chiral (S)-Alanine (left) and (R)-alanine (right) in zwitterionic form at neutral pH. In chemistry, a molecule or ion is called chiral (/ ˈ k aɪ r əl /) if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes.

  9. Ramachandran plot - Wikipedia

    en.wikipedia.org/wiki/Ramachandran_plot

    In biochemistry, a Ramachandran plot (also known as a Rama plot, a Ramachandran diagram or a [φ,ψ] plot), originally developed in 1963 by G. N. Ramachandran, C. Ramakrishnan, and V. Sasisekharan, [1] is a way to visualize energetically allowed regions for backbone dihedral angles ( also called as torsional angles , phi and psi angles ) ψ ...