Water Hardness Titration
Title: Determination of Water Hardness Using a Titrator
Purpose: To become familiar with the concept of water hardness, practice a titration technique using a titrator, and determine the hardness of the local water supply.
Procedure:
1. Gather the test tube holder, small stopcock, 10-mL syringe (titrator), and 2 thick textbooks and the LabPaq box or 5-6 thick textbooks.
2. Remove the plunger from the titrator and place it back in your LabPaq box.
3. Attach the stopcock to the tip of the titrator by placing the larger, clear, plastic end of the stopcock into the tip of the titrator and then twisting the stopcock into place. The stopcock should fit tightly into the titrator, so that the liquid will not leak.
4. Stack the textbooks on top of one another or stack two textbooks on top of the LabPaq box.
5. Clamp the test tube holder around the middle of the titrator and slide the long end under the top two books in the stack. Place a sheet of white paper next to the bottom of the stack and set the 100-mL beaker on the sheet of white paper. The end of the stopcock should be located near the top of the beaker, approximately 1 cm above to 1 cm below the top of the beaker.
6. Use the pipette to fill the titrator with 7—9 mL of distilled water.
7. Using both hands, one on the titrator and one on the stopcock, practice releasing water from the titrator into the beaker. The goal is to be comfortable releasing only one drop at a time from the titrator.
8. When you are comfortable using the titrator pour the water in the beaker down the drain, remove the titrator from the test tube clamp, and remove the stopcock from the titrator.
Thoroughly dry each of these three items with paper towels.
9. When all items are completely dry, reassemble the titration setup.
10. Put on your safety gloves and goggles.
11. With the stopcock in the closed position, fill the titrator with 9 to 10 mL of the EDTA solution.
12. Move the beaker away from the titrator and
Purpose: To become familiar with the concept of water hardness, practice a titration technique using a titrator, and determine the hardness of the local water supply.
Procedure:
1. Gather the test tube holder, small stopcock, 10-mL syringe (titrator), and 2 thick textbooks and the LabPaq box or 5-6 thick textbooks.
2. Remove the plunger from the titrator and place it back in your LabPaq box.
3. Attach the stopcock to the tip of the titrator by placing the larger, clear, plastic end of the stopcock into the tip of the titrator and then twisting the stopcock into place. The stopcock should fit tightly into the titrator, so that the liquid will not leak.
4. Stack the textbooks on top of one another or stack two textbooks on top of the LabPaq box.
5. Clamp the test tube holder around the middle of the titrator and slide the long end under the top two books in the stack. Place a sheet of white paper next to the bottom of the stack and set the 100-mL beaker on the sheet of white paper. The end of the stopcock should be located near the top of the beaker, approximately 1 cm above to 1 cm below the top of the beaker.
6. Use the pipette to fill the titrator with 7—9 mL of distilled water.
7. Using both hands, one on the titrator and one on the stopcock, practice releasing water from the titrator into the beaker. The goal is to be comfortable releasing only one drop at a time from the titrator.
8. When you are comfortable using the titrator pour the water in the beaker down the drain, remove the titrator from the test tube clamp, and remove the stopcock from the titrator.
Thoroughly dry each of these three items with paper towels.
9. When all items are completely dry, reassemble the titration setup.
10. Put on your safety gloves and goggles.
11. With the stopcock in the closed position, fill the titrator with 9 to 10 mL of the EDTA solution.
12. Move the beaker away from the titrator and