Show the stepwise dissociation of a diprotic acid, H₂CO₃, and the corresponding equilibrium equations.

Determine from the following pictures which represents a solution of a weak diprotic acid, H₂A, and which represent/s unlikely scenarios. Note that the water molecules were omitted for clarity.

Is oxalic acid a monoprotic acid? Explain.

What is the pH of a 0.15 M hydrogen selenite ion, HSeO₃⁻, if its K_a and K_b values are 4.8×10⁻⁹ and 4.2×10⁻¹², respectively?

Hydrogen sulfide (H₂S) is a toxic gas that inhibits cellular respiration. It is a weak diprotic acid and is often produced by anaerobic microbial decomposition of organic matter. A hydrogen sulfide solution has a pH of 5.85. Calculate the concentration of hydrogen sulfide (H₂S), bisulfide ion (HS⁻), and sulfide ion (S²⁻) in the solution assuming that the total concentration of the three species is 2.45×10⁻⁵ M.

Consider a solution of 0.591 M H₂CO₃. Calculate the [H₃O⁺] and pH of the solution.