1. Consult an appropriate source and determine the Concentration of each of the following species, when in Concentrated form: HCl, H2SO4, and NH3.
2. A 10mL solution of 0.010M HCl is mixed with 20mL of a 0.01M Pb2+ solution, giving a total volume of 30mL. What are the concentrations of Cland Pb2+ after the mixing? Will a precipitate of PbCl2 form? (Ksp = 1.7 x 10-5 for PbCl2 at 25oC.)
3. In the Group 2 precipitations, the Sulfide Ion (S2- ) is generated in an Acidic environment. If the H2S concentration is maintained at 0.1M and the pH = 1, what is the [S2- ] concentration? (Ka1 = 1 x 10-7 and Ka2 = 1 x 10-13 for H2S.)
4. In the Group 3 precipitations, the pH is raised by adding Ammonia. Suppose it is raised to pH = 9. What is the [S2- ] concentration under these conditions? Assume the H2S concentration is again 0.1M.