A student wanted to determine the molar concentration of acetic acid in a commercial vinegar sample. He used a volumetric pipet to deliver 3.00 mL of vinegar to an Erlenmeyer flask, added about 30 mL orf water and 3 drops of phenolphthalein indicator. He performed titration and obtained the following data
Flask Initial Volume (0.0997 M NaOH) mL Final Volume (0.0997 M NaOH) mL
1 50.00 25.10
2 25.10 0.35
3 50.00 25.00
a. Determine the molarity of acetic acid in the vinegar sample.
b. Convert molar concentration to % Acetic acid
c. Using tables of pK values of indicators, comment on the use of phenolphthalein as the indicator on the titration of the weak acid, acetic acid by a strong base, NaOH.