Experiment 11 - Laboratory Examination - Acid-Base Titration

Procedure:

Part B - Acid-Base Titration

1. Obtain about 100 mL of the NaOH solution in a clean and dry beaker.
2. Fill the buret with the base solution.
3. Transfer about 75 mL of the potassium hydrogen phthalate, HKC₈H₄O₄, solution into a clean and dry beaker.
4. Pipet 25.00 mL of the acid solution into an erlenmeyer flask. Add about 3 drops of phenolphthalein indicator solution to the acid in the flask.
5. Add the NaOH solution in the buret to the potassium hydrogen phthalate, HKC₈H₄O₄, solution in the flask until a pink end point is reached.
6. Read the buret carefully to determine the quantity of base used to reach the end point. Record the volume of the NaOH solution used.
7. Repeat steps 4 to 6 until two results are obtained which agree within +/- 0.10 mL.
8. Enter your data clearly on the datasheet and present calculations to show how you determined the concentration of the NaOH solution in moles/L.