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Online Chemistry Labs | Learning Objectives

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.

Vitamin C Analysis 

Learning Objectives:

  1. Become familiar with the concept of analysis by counting drops of titrant in a titration to reach a colored endpoint.
  2. 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.
  3. Be able to use ratios to calculate the amount of vitamin-C contained in a larger volume of known concentration.
  4. 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.