Ion product for water

The molar concentration of water, 55.56 mol/L, is too great to be significantly affected by dissociation. It therefore is considered to be essentially constant. This constant may then be incorporated into the dissociation constant K to provide a useful new constant termed the ion product for water. The relationship between and is shown below ... 

Some references do not list values of Kb or pATb for amines. Instead, they list values of Ka or pKa for the conjugate acid, which is the ammonium ion. We can show that the product of Ka for the ammonium ion and Kb for the amine is Xw> the ion product for water, which is 1(T14 at room temperature. This is true for any conjugate acid-base pair (see Section 1-13B). 

Because the H2O is pure, its activity is 1, so we do not include its concentration in the equilibrium constant expression. This equilibrium constant is known as the ion product for water and is usually represented as K. ... 

Ion product for water An equilibrium constant for the ionization of water,... 

The product of hydronium and hydroxide ion concentration in pure water is referred to as the ion product for water. 

Pure water at room temperature has a hydronium ion concentration of 1.0 X 10 M. One hydroxide ion is produced for each hydronium ion. Therefore, the hydroxide ion concentration is also 1.0 X 10 M. The product of hydronium and hydroxide ion concentration (1.0 X 10 is the ion product for water. 

Given the following standard reduction potentials, calculate the ion-product, for water at 25 C ... 

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