Lab 7.docx - Mejia 1 Determination of Acetic Acid...

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Determination of Acetic Acid Concentration in Vinegar Using Titration
Professor Xin Wu, Shelia Fox, Jesse Fox
Submitted by
Marta Mejia
March 9, 2020

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Introduction
The goal of this experiment is to find the precise acetic acid component in vinegar. In order for
results to be found titration will be conducted throughout the experiment. Titration occurs with a
solution called sodium hydroxide for three repetitions. On the first activity an acid percent is
found using vinegar. The second activity, repetitions will made but with a different vinegar. For
the third activity the pk of an acid is found.
Materials
 25-mL Erlenmeyer flask
 Electronic balance
 Disposable pipet
 Phenolphthalein indicator solution
 1% Sodium hydroxide solution, 1M
 Plastic cup, 1.25 oz
 Plain sheet of white paper
 Vinegar sample
 Vinegar, acetic acid solution
 10-mL graduated cylinder
 Syringe, 10 mL
Procedure/Methods
For safety during this lab goggles, gloves, and apron must be worn. There is a total of three
activities in this lab. The first part requires vinegar with sodium hydroxide to titrate. First, a

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graduated cylinder was put on a balance and teared. Next, 5 mL of vinegar was put inside the
gradated cylinder using a pipet and results were placed on Figure 1. The solution was then put
into an Erlenmeyer flask with an addition of two drop of phenol phthalein. The solution was
mixed and from there 10 mL were put in a small cup to fill a syringe with 1M of NaOH. The
volume was recorded on Figure 1 to the nearest 0.1 mL. The remaining solution in the flask was
put on top of a plain sheet of paper. This was done to observe a different color change solution.
While the NaOH that was still in the syringe was also added with 0.5 increments and constantly
being mixed to see a change in color. The results were all recorded on Figure 1. The solution was