Autoionization proces

This reaction, which is an example of autoionization, proceeds to the right to only a very tiny extent because water is such a weak acid and base. To write an equilibrium constant expression for this reaction, we again consider the concentration of water itself to be a constant, which we incorporate into the value of K. We get another type of constant, called the water ionization constant and denoted K. ... 

Conventional associative ionization (AI) occurring at ambient temperature proceeds in two steps excitation of isolated atoms followed by molecular autoionization as the two atoms approach on excited molecular potentials. In sodium for example [44]... 

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