Title: Titration for Acetic Acid in Vinegar
Purpose: The objectives in this lab were to develop familiarity with the concepts and techniques of titration and to determine the concentration of an acetic acid solution in vinegar.
Procedure:
Data Tables: Data Table 1: Quantity of NaOH needed to Neutralize 5 mL of Acetic Acid Brand of Vinegar Used: heinz Label Notes: none | | Initial NaOH reading(Interpolate to 0.1 mL) | Final NaOH reading(Interpolate to 0.1 mL) | Volume of NaOH used | Trial 1 | 9.5 | 1.3 | 8.2 | Trial 2 | 9.6 | 1.4 | 8.2 | Trial 3 | 9.7 | 1.4 | 8.3 | Average volume of NaOH used: | 8.23 |
Observations:
A. Calculate the average number of mL of NaOH used for the 3 trials and record.
8.23
B. Calculate the Normality of the vinegar using the previously given equation.
Na = (Nb)(Volumeb)
(Volumea)
.82M
C. Calculate the mass of the acetic acid in grams using the previously given equation.
Massa = (Na)(GMWa)
49.8g
D. Calculate the percentage of acetic acid using the previously given equation.% Acid =Massa(g/L)x1001000g/L=
4.98%
Questions:
A. What is the average % acetic acid in your vinegar sample? Standard vinegar is 5% acetic acid. How does your result compare with the standard? Average % acetic acid is slightly above 4%. it is less than standard
B. Why is it better to use white vinegar rather than dark vinegar for this titration?
Because white vinegar consists of only acetic acid and water and dark has other things added to it C. Write a balanced equation for the neutralization of acetic acid with NaOH. CH3COOH + NAOH =.CH3COONA +H2O
D. How would your results have differed if the tip of the burette was not filled with sodium hydroxide before the initial volume reading was recorded? You would think there was more NaOH than there actually was
E. How would your results have differed if you had over-titrated, i.e. added NaOH beyond