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Pre-Lab calculations.
1) Determine the pH of a 0.10M HC2H3O2 (HAc) solution.
2) Determine the pH of a 0.10M NH3 solution.
3) Determine the pH of a 0.10M HC2H3O2 (HAc) and 0.050M sodium acetate solution. (Same as 1 except adding in moles of Na1C2H3O2 or a common ion effect problem).
4)Determine the pH of a 0.10M NH3 and 0.050M ammonium chloride solution. (Again another common ion effect problem).
5) Determine how many grams of sodium acetate you need to weigh out to get 100.ml of a 0.050M sodium acetate solution. (Hint: don't worry about the HAc solution, just assume you are only making the sodium acetate solution by itself).
6) Determine how many grams of ammonium chloride you need to weigh out to get 100.ml of a 0.050M ammonium chloride solution. (Again assume you are only making the ammonium chloride solution by itself).
Lab Diections
1) Get a computer and Lab Pro equipment including a pH probe. Connect correctly and open up a lab that allows you to read pH values.
2) Obtain approximately 30ml of the 0.10M HAc solution. Determine the pH of this solution and record in data table. Wash off the pH probe with DI water.
3) In a 150.ml or 250.ml beaker, pour 100.ml of the 0.10M HAc solution (measured via graduated cylinder) into the beaker.
4) Weigh out the desired mass of sodium acetate you calculated in the Pre-lab calculations. Place into the HAc solution in the 150.ml or 250.ml beaker. Stir to dissolve.
5) Once dissolved, determine the pH of the solution and record in the data table. Wash off the pH probe with DI water.
Steps 6-9: Repeat Steps 2-5 for 0.10M NH3 and 0.050M ammonium chloride solutions.