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  2. Electron-withdrawing group - Wikipedia

    en.wikipedia.org/wiki/Electron-withdrawing_group

    Electron-withdrawing groups exert an "inductive" or "electron-pulling" effect on covalent bonds. The strength of the electron-withdrawing group is inversely proportional to the pKa of the carboxylic acid. [2] The inductive effect is cumulative: trichloroacetic acid is 1000x stronger than chloroacetic acid.

  3. Field effect (chemistry) - Wikipedia

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

    With respect to acidity, a common trend to note is that, inductively, an electron-withdrawing substituent in the vicinity of an acidic proton will lower the pKa (i.e. increase the acidity) and, correspondingly, an electron-donating substituent will raise the pKa. [7] The reorganization of charge due to field effects will have the same result.

  4. Inductive effect - Wikipedia

    en.wikipedia.org/wiki/Inductive_effect

    If the electronegative atom (missing an electron, thus having a positive charge) is then joined to a chain of atoms, typically carbon, the positive charge is relayed to the other atoms in the chain. This is the electron-withdrawing inductive effect, also known as the -I effect. In short, alkyl groups tend to donate electrons, leading to the +I ...

  5. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    The electron-withdrawing effect of the substituent makes ionisation easier, so successive pK a values decrease in the series 4.7, 2.8, 1.4, and 0.7 when 0, 1, 2, or 3 chlorine atoms are present. [49] The Hammett equation , provides a general expression for the effect of substituents.

  6. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    For meta-directing groups (electron withdrawing group or EWG), σ meta and σ para are more positive than σ’. (The superscript, c, in table denotes data from Hammett, 1940. [11] [page needed]) For ortho-para directing groups (electron donating group or EDG), σ’ more positive than σ meta and σ para.

  7. Carbanion - Wikipedia

    en.wikipedia.org/wiki/Carbanion

    Triflidic acid, with three strongly electron-withdrawing triflyl groups, has an estimated pK a well below −10. On the other end of the scale, hydrocarbons bearing only alkyl groups are thought to have pK a values in the range of 55 to 65. The range of acid dissociation constants for carbon acids thus spans over 70 orders of magnitude.

  8. 21 Vintage Photos of Christmas Window Displays From the Last ...

    www.aol.com/21-vintage-photos-christmas-window...

    Take a trip down memory lane with by looking at these incredible photos of Christmas window displays from the last 100 years,

  9. Captodative effect - Wikipedia

    en.wikipedia.org/wiki/Captodative_effect

    The captodative effect is the stabilization of radicals by a synergistic effect of an electron-withdrawing substituent and an electron-donating substituent. [2] [3] The name originates as the electron-withdrawing group (EWG) is sometimes called the "captor" group, whilst the electron-donating group (EDG) is the "dative" substituent. [3]