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In this lab, you will determine the concentration of acetic acid in vinegar using a 0.110 M NaOH standard solution and an acid-base indicator, phenolphthalein.
To perform this experiment you will first need to dilute the vinegar by one tenth of the original concentration. Next, add the indicator and then add NaOH slowly to the diluted vinegar solution. Once all the acetic acid has reacted with the base, the first excess drop of NaOH will cause the indicator in the vinegar solution to turn pink. Calculate the concentration of the acetic acid in your vinegar sample to three significant figures.
Now check your answer using the Virtual Lab.