What challenges would you encounter with the titration if

Question

Titration for Acetic Acid in Vinegar

This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment's questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students' writing of lab reports by providing this information in an editable file which can be sent to an instructor.

Exercise 1: Determining the Concentration of Acetic Acid

Data Table 1.NaOH Titration Volume.

	Initial NaOH Volume (mL)	Final NaOH Volume (mL)	Total volume of NaOH used (mL)
Trial 1	9	5.6	3.4
Trial 2	5.6	3.2	2.4
Trial 3	3.2	0.2	3.0
	Average Volume of NaOH Used (mL) :

Data Table 2. Concentration of CH₃COOH in Vinegar.

Average volume of NaOH used (mL)	Concentration CH3COOH in vinegar (mol/L)	% CH3COOH in vinegar

Using the following equation, determine the average concentration (moles per liter) of acetic acid (CH3COOH) present in your vinegar. Record the concentration in Data Table 2.

M CH₃COOH = L NaOH x (mol NaOH)/L x (1 mol CH₃COOH)/(1 mol NaOH) x 1/(0.005 L)

Using the following equation, determine % concentration (mass percent) of acetic acid (CH₃COOH) in the vinegar and record it in Data Table 2.

Note: The density of vinegar is 1.00 g/ml and the molecular mass of vinegar is 60.05 g/mol.

% CH₃COOH = (mol CH₃COOH)/(1 LVinegar) x (1 L)/1000mL x (1 mL Vinegar)/(1.00 g Vinegar) x (600 g CH₃COOH)/(1 mol CH₃COOH)x 100 %

Questions

A. The manufacturer of the vinegar used in the experiment stated that the vinegar contained 5.0% acetic acid. What is the percent error between your result and the manufacturer's statement?

B. What challenges would you encounter with the titration if you had used apple cider vinegar or balsamic vinegar as the analyte instead of white vinegar?

C. How would your results have differed if the tip of the titrator was not filled with NaOH before the initial volume reading was recorded? Explain your answer.

D. How would your results have differed if you had over-titrated (added drops of NaOH to the analyte beyond the stoichiometric equivalence point)?

E. If a 7.0 mL sample of vinegar was titrated to the stoichiometric equivalence point with 7.5 mL of 1.5M NaOH, what is the mass percent of CH₃COOH in the vinegar sample?

F. Why is it important to do multiple trials of a titration, instead of only one trial?