1. I-Neutralization Curves: Potentiometric Methods Dr. Prem D. Sattsangi Copyright © 2009

2. Unknown Sample (Acetic Acid) UK #1UK #1 Diluted to 100 mL

3. Pippette UK into 250 mL beaker

4. Add 25 mL of distilled H 2 0 Added 25 mL waterAdded 3 drs phenolphthalein

5. Record Initial pH of the Solution First pH reading

6. Titrate to the Endpoint End point Graph and pH readings

7. Add More NaOH until pH becomes ~12 Few mL later pH Reaading

9. Calculation of M (Acetic acid) Equation: CH 3 COOH + NaOH  CH 3 COONa + H 2 O Data: Acetic acid VOLUME = 25.00 mL NaOH (0.245M) VOLUME = 5.5 mL M of AcOH in 100 mL Volumetric = 0.054M Moles of AcOH in 100 mL = 0.054 mol x 0.100 L = 0.0054mol In U.K. L

11. Calculation of M (H 3 PO 4 ) Equation: H 3 PO 4 + NaOH  H 2 PO 4 + + H 2 O Data: H 3 PO 4 VOLUME = 25.00 mL NaOH (0.245M) VOLUME = 7.2 mL M of H 3 PO 4 in 100 mL Volumetric = 0.071M Moles of H 3 PO 4 in 100 mL = 0.071 mol x 0.100 L = 0.0071mol L