What Are the Steps and Considerations for Titration of Vinegar?

[Quincy]

Homework Statement

A solution of household vinegar (a mixture of acetic acid and water) is to be analyzed. A pipet is used to measure out 10.0 mL of the vinegar, which is placed in a 250 mL volumetricflask. Distilled water is added until the total volume of solution is 250 mL. A 25.0 nL portion of the diluted solution is measured out with a pipet and titrated with a standard solution of sodium hydroxide.

The neutralization reaction is as follows:

HC₂H₃O₂ (aq) + OH^- (aq) --> C₂H₃O₂^- (aq) + H₂O (l)

1) It is found that 16.7 mL of 0.0500 M NaOH is needed to titrate 25.0 mL of the diluted vinegar. Calculate the molarity of the diluted vinegar.
.0167 L NaOH x .0500 mol NaOH / 1 L NaOH = 8.35 x 10^-4 mol NaOH

8.35 x 10^-4 mol NaOH x 1 mol HC₂H₃O₂ / 1 mol NaOH = 8.35 x 10^-4 mol HC₂H₃O₂


8.35 x 10^-4 mol HC₂H₃O₂ / .0250 L = 0.0334 M HC₂H₃O₂

2) Calculate the molarity of the household vinegar.

250 / 25 = 10

8.35 x 10^-4 mol HC₂H₃O₂ x 10 = 8.35 x 10^-3 mol HC₂H₃O₂

8.35 x 10^-3 mol HC₂H₃O₂ / .0100 L =
0.835 M HC₂H₃O₂

3) The household vinegar has a density of 1.05 g/mL. Calculate the percent by mass of acetic acid in the household vinegar.

1.05 g/mL x 10 mL = 10.5 g HC₂H₃O₂ + H₂O

8.35 x 10^-3 mol HC₂H₃O₂ x 60.04 g/mol =
0.501 g HC₂H₃O₂

(0.501 g HC₂H₃O₂/ 10.5 g) x 100 = 4.77% HC₂H₃O₂

 

[Borek]

Looks OK to me.

 

[Blueshift5]

I would like to point out a few things about this titration experiment. Firstly, it is important to use accurate and precise measuring tools, such as a pipet and a volumetric flask, to ensure that the results are reliable. Secondly, it is crucial to perform multiple trials to obtain an average value and to check for consistency in the results. This will help to reduce any errors and increase the accuracy of the final measurement. Additionally, it is important to properly label all solutions and to keep track of the units and conversions used in the calculations. Finally, it is also important to be aware of any potential sources of error, such as impurities in the solutions or incorrect measurements, and to take steps to minimize their impact on the results. Overall, this experiment provides a valuable opportunity to practice important laboratory skills and to understand the principles of titration and acid-base reactions.