**Background:**

This experiment is an introductory level lab that introduces the
student to the analysis of the vitamin-C content of unknown
samples. No background in analyses or stoichiometry is assumed. The
student is provided with a standard solution of known vitamin-C
content, and the dropwise titration with a titrant to a colored
endpoint is performed to establish a comparative method for
determining other solutions. Next the student is provided unknown
drink and juice samples to determine by ratio to the vitamin-C
standard. In addition to calculating the concentration of vitamin-C
in each unknown, student calculate the amount of vitamin-C in a
full drink container of known volume and in the whole fruit given
the fraction of the fruit that was used to produce the titrated
sample.

**Learning Objectives:**

- Become familiar with the concept of analysis by counting drops
of titrant in a titration to reach a colored endpoint.
- Be able to compare the unknown solutions to the standard by
comparing the drops of titrant used to consume the vitamin-C in
each solution.
- Be able to use ratios to calculate the amount of vitamin-C
contained in a larger volume of known concentration.
- Be able to calculate the amount of vitamin-C in an entire fruit
after analyzing a small sample that represents a known fraction of
the whole fruit.