Consider formic acid, HCHO2 (Ka = 1.9x10-4) and its conjugatebase, CHO2-.
a) A buffer is prepared by dissolving 25.0 grams of sodiumformate in 1.30 L of a solution of 0.660 M formic acid. Assume thevolume remains constant after dissolving the sodium formate.
  i) Calculate the pH of this buffer.
  ii) Calculate the pH after 0.100 mole of nitricacid is added to this buffer.
  iii) Calculate the pH after 10.0 grams of potassiumhydroxide is added to this buffer.
  iv) What is the buffer capacity of this buffer?
b) 35.0 mL of 0.739 M formic acid is titrated with 0.431 Mpotassium hydroxide.
  i) What is the pH of the formic acid solutionbefore titration begins?
  ii) How many milliliters of KOH is required forthis titration to reach its equivalence point?
  iii) What is the pH of the solution after 10.0 mLof KOH has been added?
  iv) What is the pH of the solution halfway toequivalence?
  v) What is the pH of the solution at theequivalence point?
