Part 1: First Halfway point Ka₁ = 2.34x10 Second Halfway Point: Ka, = 631×10' Moles of NaOH at the Equivalence Point First Equivalence Point Second Equivalence Point 1.1826 x 10 mol 1444 107 Moles of KHP at the Equivalence Point First Equivalence Point Same as the moles of NaOH¸ = 1.1826 × 10-ª mol Second Equivalence Point: Same as the moles of NaOH= 2.444 × 107 Molar mass of KHP =204.12 g/mol Mass of KHP used at first equivalence 2.45 x 10 g Mass of KHP used at first equivalence = 4.99x10 g Part 2: First Halfway point: Ka₁ = 2.34x10 Second Halfway Point: Ka, 631-10 Males of NaOH at the Equivalence Point First Equivalence Point 1.1826 x 10 mol Second Equivalence Point 2.444 x 10 Moles of KHP at the Equivalence Point First Equivalence Point Same as the moles of NaOH, = 1.1826 x 10 mol Second Equivalence Point: Same as the moles of NaOH= 2.444 x 10- Molar mass of KHP=204.22 g/mol Mass of KHP used at first equivalence = 1.1826 x 10' mol

1. Compare your pKa, Ka and molar mass from your experiment to the expected values for KHP. How well do they compare? What might account for the differences?

2. Based on your results in Part 1, is the method used reliable in determining pKa, Ka and molar mass of a weak acid? Explain.

3. Discuss your thinking on how you determined the identity of your unknown. Were there two (or more) acids that were difficult for you to distinguish between? If so, how did you makeyour final decision?