How can one create an experiment that will deteremine the Ksp of a solid like Ca(OH)2
1. Pour 50 mL of saturated calcium hydroxide Ca(OH)2 solution into a 125 mL beaker.
DO NOT shake up the stock bottle. It is saturated and solid will be on the bottom.
2. Fold a piece of filter paper into a cone and fit it into a funnel. Your instructor will demonstrate the
folding technique.
3. Pour your calcium hydroxide Ca(OH)2 solution into the paper cone and allow the solution to drip
into a dry 250 mL Erlenmeyer flask.
4. Remember to cover this flask with a 30 mL beaker when you are not pipetting from it.
5. Measure the temperature of your solution with a dry thermometer.
6. Pour 75 mL of EDTA solution into a dry 125 mL Erlenmeyer flask.
7. Rinse a clean burette three times with 2-3 mL portions of this EDTA solution.
8. Fill the burette with the EDTA solution.
9. Into a 250 mL Erlenmeyer flask:
Pipette 10 mL of the filtered calcium hydroxide Ca(OH)2 solution.
Add 2 drops of Eriochrome Black T indicator to the 250 mL Erlenmeyer.
10. Titrate the calcium hydroxide Ca(OH)2 solution with the EDTA solution until the indicator
changes form reddish to a pure blue. Careful, a purplish (reddish-blue) color is not the end point,
but it does show that your are near the end point.
11. Repeat the titration two more times.