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Title: explain how the ionization of a strong acid differs from that of a weak acid in a solution.? Post by: buffzyzz on Apr 15, 2013 Give an example of a strong acid and a weak acid. Show what Ions form when each is dissolved in water.
Title: explain how the ionization of a strong acid differs from that of a weak acid in a solution.? Post by: figment5 on Apr 15, 2013 Bear with me as I think this out:
Arrhenius definition: Acids are compounds that produce [H+] in water. Bronsted-Lowry definition: Acids release [H+] in water. Either way, you still get [H+] in water. Ionization = formation of ions. Water is amphoteric and can act either as an acid or base. Ionization of water: 2 H20(l) --> H3O+(aq) + oH- Kw = [H3O+][OH-] = 1.0x10^-14 (hydronium)(hydroxide) [H30+] or [OH-] by itself is 1.0x10^-7 So the strong the acid, the more H30+ it produces and the lower the pH is because it ionizes almost completely in water. Example 1: a strong acid such as HCI ionized almost completely in water. HCI(aq) + H2O ----> Cl- (aq) + H3O (aq) A 0.1M solution of HCI would contain about 0.1M H3O+, 0.1MCl-, and almost no HCl. pH= -log [H3O+] = -log(0.1) = 1.0pH Example 2: Week acids ionize much less. In HF, for example, only about 8% of the molecules are ionized at any given time. HF(aq) + H2O ---> F- (aq) + H30+ (aq) A 0.1M solution of HF would contain about 0.008M H3O+, 0.0008M F-, and 0.09M HF and has the pH of about 2.0. |