Tartaric acid is found in many fruits, including grapes, and is partially responsible for the dry texture

Question:

Tartaric acid is found in many fruits, including grapes, and is partially responsible for the dry texture of certain wines. Calculate the pH and the tartarate ion (C4H4O62-) concentration for a 0.250 M solution of tartaric acid, for which the aciddissociation constants are listed in Table 16.3. Explain any approximations or assumptions that you make in your calculation.