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Part B.1. A drop of NaOH titrant, dispensed from the buret, adheres to the wall of the Erlenmeyer flask but is not washed into the vinegar with the wash bottle. Does this error in technique result in the reported percent of acetic acid being too high, too low, or unaffected? Explain.

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Chlidonias

In the titration of acetic acid with a strong base NaOH, the concentration of acetic acid is determined using the volume and molar concentration of NaOH used for titrating the vinegar solution. NaOH and acetic acid react in 1:1 mole ratio.

[tex]CH_{3}COOH(aq) + NaOH(aq)-->CH_{3}COONa(aq)+H_{2}O(l)[/tex]

When a drop of the strong base, dispensed from the buret sticks to the walls of the Erlenmeyer flask but is not washed into the flask containing vinegar, it means that the recorded value of NaOH dispensed will be higher than the actual value required for the titration. So, the reported moles of acetic acid calculated from the moles of NaOH used for the titration will be higher. So, the mass percent reported will be higher than the actual value.