Chem 163, Quiz 2, 10 points
Name ___________________________
1. (3 points) At 25C, 500.0 mL of water dissolves 0.311 g of PbI2. (Molar Mass = 461.00 g/mol)
Calculate the solubility______________________ molar solubility______________________ ,
and Ksp_______________________ for Lead(II)Iodide.
2. (2 points) For the titration of hypochlorous acid (HClO) with sodium hydroxide:
a. What is the pH of the solution made by titrating 25.0 mL of 0.280M hypochlorous acid
(HClO) Ka = 3.0 x 10-8, with 50.0 mL of 0.140 M NaOH?_____________________
b. What point in the titration is this at, the Midpoint or Equivalence point?
c. What are the concentrations of butanoic acid ______________________and its
conjugate base ______________________in the solution at this point?
3. (2 points) What are the pH, and concentration of H2SO3, in a solution of 0.35 M Na2SO3?
4. (3 points) Draw the titration curve for a weak base with a strong acid. Label all parts of the graph
(buffer region, midpoint, equivalence point, axes). Include estimated pH values on your graph
for the buffer region, equivalence point, and midpoint.
a. What species are present at the midpoint, and are any species equal to each other?
_________________________
b. What species are present at the equivalence point, and are any species equal to each
other? __________________________