What is acid dissociation?

Question

please explain.

Does it prevent a reading of pH 7 from being obtained following dilution of acid or base to a concentration of 10-7 mol dm-3?

please help!

Answer 1

The acid dissociation constant indicates the extent of dissociation of H+ ions from an acid. This dissociation directly effects the pKA, which in turn effects the pH. Being an equillibrium constant, the dissociation is determined in the free energy (delta G).

For example, suppose that the protonated (AH) form donates a hydrogen bond AH\cdotsX to another atom X, which the de-protonated form cannot do (since it has no hydrogen left). The protonated form is favored by having a hydrogen bond, so the pKa increases (the Ka decreases). The magnitude of the pKa shift can even be determined from the change

Answer 2

The web site below properly answers this question:

http://www.wellesley.edu/Chemistry/chem120/diluteacids.html