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

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

Pippette UK into 250 mL beaker

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

Record Initial pH of the Solution First pH reading

Titrate to the Endpoint End point Graph and pH readings

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

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

Calculation of M (H 3 PO 4 ) Equation: H 3 PO 4 + NaOH  H 2 PO H 2 O Data: H 3 PO 4 VOLUME = 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 = mol x L = mol L