Titration of % of Acetic Acid in Vinegar

Lab Report 5

Titration for the Percentage of Acetic Acid in Vinegar

NAME: _________________________________

Objectives:

1.

2.

Background Information:

What is the active ingredient in household vinegar? What are its
molecular formula and mass? What is its percent (or range of percents)
in commercially available vinegar?

What is titration? Why is it used?

How is the endpoint of a titration determined?

What is an indicator?

NOTE: We have not discussed the concept of normality in our class. In
some instances, normality and molarity can be used interchangeably.
This is one of those cases. (For a review of molarity, see Chapter 4 in
your text.)

Procedure:

(This is where you should give a brief summary of what you will do.)

Observations/Data:

Brand Name of Vinegar Used: _________________________________

Percent on Label: ___________________________________________

Trial Number: 1 2
3 Average

Drops of NaOH Used:

Calculations:

Normality of vinegar: _______________________________________

Mass of acetic acid in grams: _________________________________

Percentage of acetic acid in your vinegar: ______________________

Percent error: ____________________________________________

Percent error is calculated according to the following formula:

% error = | theoretical value – actual value| x 100%

theoretical value

The theoretical value you use should be the percent on the label of your
vinegar. The actual value is the percent you determined.

Note: We are using the percent on the label as the theoretical value
because the food manufacturers are supposed to be truthful in their
labeling and because their equipment is far better than what you have in
the lab kit. It is possible, however, that occasionally errors can
occur and the vinegar was labeled incorrectly. This is unlikely,
though.

Questions:

1.

2.

Conclusions: