Finding Vitamin C or Ascorbic Acid

There are several ways you can use a titration to determine the amount of vitamin C (ascorbic acid) in juice, fruit, or vegetables. One of the best methods is to use an iodometric titration. An acid-base titration isn't optimal because there are other acids besides vitamin C in the produce that can affect the results. A simple iodine titration works, where you complex the iodine with starch to give a visible endpoint. The iodate method basically is the same, except the chemical species is more stable, so you can get a more accurate value.

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