Solubility Product Constant

...There is a ......
Return to ....... Chem114 SYLLABUS

"Insoluble" things are dissolving all around us.
For example, degradation of mountains proceeds by a combination of wind, water, heat and cold and involves both chemical and physical processes.

Ultimately though, it boils down to

When you go to the beach, why do you lie on grains of SiO2 rather than NaCl?

ksppbi2.jpg (4417 bytes)

This experiment deals with the Ksp of Lead Iodide, PbI2.
You will measure the solubility of PbI2 in a 0.1 M KNO3 solution.

  • You will make 4 solutions from known amounts of Pb(NO3)2 and KI.
  • You will make a fifth solution by dissolving pure PbI2.
  • In each, you will measure, spectroscopically,  the [I-] left in solution.
  • This is done by oxidizing the colorless dissolved iodide ions into the colored iodine.
  • From this you can calculate the [Pb+2] and the Ksp.
  • The 5 calculated Ksp should be the same within experimental error.

Some Additional Notes

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