Practice: Sulfurous acid, H_{2}SO_{3}, represents a diprotic acid with a K_{a1} = 1.6 × 10^{−}^{2} and K_{a2} = 4.6 × 10^{−}^{5}. Calculate the pH when given 0.200 M H_{2}SO_{3}.

**Diprotic Acids** and **Bases** require ICE Charts to determine their pH and pOH respectively

Concept #1: Sulfuric acid represents the only strong diprotic acid

Example #1: Calculate the pH of a 0.0550 M H_{2}SO_{4} solution. K_{a1} = 1.0 x 10^{3} and K_{a2} = 1.2 x 10^{-2}.

Example #2: Calculate the pH of a 0.115 M carbonic acid, H_{2}CO_{3,} solution. K_{a1} = 4.3 x 10^{-7} and K_{a2} = 5.6 x 10^{-11}.

Example #3: Determine the [CO_{3}^{2–}] when given 0.115 M carbonic acid, H_{2}CO_{3}, solution. K_{a1} = 4.3 x 10^{-7} and K_{a2} = 5.6 x 10^{-11}.

Practice: Sulfurous acid, H_{2}SO_{3}, represents a diprotic acid with a K_{a1} = 1.6 × 10^{−}^{2} and K_{a2} = 4.6 × 10^{−}^{5}. Calculate the pH when given 0.200 M H_{2}SO_{3}.

Practice: Determine the pH of 0.115 M Na_{2}S. Hydrosulfuric acid, H_{2}S, possesses K_{a1} = 1.0 × 10^{−}^{7} and K_{a2} = 9.1 × 10^{−}^{8}.