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Homework Statement
A student wished to determine the percent of acetic acid in commercial vinegar products. Brand X was selected. Three 20.0mL volumes were titrated with a 2.20mol/L sodium hydroxide solution until the indicator phenolphthalein turned pink. The density of acetic acid is 1049.2kg/m3. The data gathered in the experiment is recorded below. Calculate the volume percent of acetic acid in vinegar.
Initial burette reading - Vi = 0.00mL
Volume reading first trial titration - V1 = 8.82mL
Volume reading second titration - V2 = 16.84mL
Volume reading third titration - V3 = 24.80mL
Concentration of the NaOH - c = 2.20mol/L
Volume of vinegar - Vvin = 20.0mL
ANSWER: 5.03%
The Attempt at a Solution
I have done titration calculations before, but something about three titrations confuses me. I started with getting the mol of NaOH then using that to get the mole of acetic acid and from there using V3 to get the volume then dividing that by the volume of vinegar x 100%. I am not sure where to use the density.