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How OH- ions act as as a lewis base?
G. N. Lewis suggested the reaction between H+ and OH- ions. In the Bronsted model, the OH- ion is the active species in this reaction it accepts an H+ ion to form a covalent bond. In the Lewis model, the H+ ion is the active species it accepts a pair of electrons from the OH- ion to form a covalent bond.


In the Lewis theory of acid-base reactions, bases donate pairs of electrons and acids accept pairs of electrons.
          A Lewis acid is therefore any substance, such as the H+ ion, that can accept a pair of non bonding electrons. In other words, a Lewis acid is an electron-pair acceptor.
         A Lewis base is any substance, such as the OH- ion, that can donate a pair of nonbonding electrons. A Lewis base is therefore an electron-pair donor.
donor.

One advantage of the Lewis theory is the way it complements the model of oxidation-reduction reactions. Oxidation-reduction reactions involve a transfer of electrons from one atom to another, with a net change in the oxidation number of one or more atoms.


The Lewis theory suggests that acids react with bases to share a pair of electrons, with no change in the oxidation numbers of any atoms. Many chemical reactions can be sorted into one or the other of these classes. Either electrons are transferred from one atom to another, or the atoms come together to share a pair of electrons.


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