enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    Do replacement reactions of aryl diazonium salts (dediazotizations) predominantly undergo S N 1 or a radical mechanism? [6] Can an electrochemical cell reliably perform organic redox reactions? [7] Which "classic organic chemistry" reactions admit chiral catalysts?

  3. Addition reaction - Wikipedia

    en.wikipedia.org/wiki/Addition_reaction

    In organic chemistry, an addition reaction is an organic reaction in which two or more molecules combine to form a larger molecule called the adduct. [1] [2] An addition reaction is limited to chemical compounds that have multiple bonds. Examples include a molecule with a carbon–carbon double bond (an alkene) or a triple bond (an alkyne).

  4. Equilibrium chemistry - Wikipedia

    en.wikipedia.org/wiki/Equilibrium_chemistry

    However, in the case of redox reactions it is convenient to split the overall reaction into two half-reactions. In this example Fe 3+ + e − ⇌ Fe 2+ Ce 4+ + e − ⇌ Ce 3+ The standard free energy change, which is related to the equilibrium constant by = ⁡ can be split into two components,

  5. Marcus theory - Wikipedia

    en.wikipedia.org/wiki/Marcus_theory

    In outer sphere redox reactions no bonds are formed or broken; only an electron transfer (ET) takes place. A quite simple example is the Fe 2+ /Fe 3+ redox reaction, the self exchange reaction which is known to be always occurring in an aqueous solution containing the aquo complexes [Fe(H 2 O) 6] 2+ and [Fe(H 2 O)6] 3+.

  6. Outer sphere electron transfer - Wikipedia

    en.wikipedia.org/wiki/Outer_sphere_electron_transfer

    For most reactions, the rates increase with increased driving force. A second aspect is that the rate of outer sphere electron-transfer depends inversely on the "reorganizational energy." Reorganization energy describes the changes in bond lengths and angles that are required for the oxidant and reductant to switch their oxidation states .

  7. List of chemistry mnemonics - Wikipedia

    en.wikipedia.org/wiki/List_of_chemistry_mnemonics

    A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.

  8. Butler–Volmer equation - Wikipedia

    en.wikipedia.org/wiki/Butler–Volmer_equation

    The upper graph shows the current density as function of the overpotential η . The anodic and cathodic current densities are shown as j a and j c, respectively for α=α a =α c =0.5 and j 0 =1mAcm −2 (close to values for platinum and palladium).

  9. Woodward–Hoffmann rules - Wikipedia

    en.wikipedia.org/wiki/Woodward–Hoffmann_rules

    Thermolysis converts 1 to (E,E) geometric isomer 2, but 3 to (E,Z) isomer 4.. The Woodward–Hoffmann rules (or the pericyclic selection rules) [1] are a set of rules devised by Robert Burns Woodward and Roald Hoffmann to rationalize or predict certain aspects of the stereochemistry and activation energy of pericyclic reactions, an important class of reactions in organic chemistry.