Chemistry Notebook
Name:
Date: 2/17/25
Experiment #: 4
Title: Molarity Vit C
Purpose:
The purpose of this experiment is to determine the concentration of ascorbic acid (vitamin C) in
oranges, lemons, and limes by using a titration mixture of iodine, starch, and ascorbic acid, by
reaching the endpoint and calculating the molarity.
Procedure:
Experiment #1: Vitamin C Concentration in Iodine
1. A sheet of weighing paper was placed on a balance and the balance was tared to 0 g.
2. 0.5 g of ascorbic acid was placed on the weighing paper and measured on the balance.
3. The ascorbic acid was placed into a volumetric flask,
4. 250 mL of water was added using a funnel into the volumetric flask.
5. The flask was swirled lightly and the ascorbic acid was dissolved.
6. A buret with 0.01 M solution of iodine was prepared for titration.
7. A 10 mL sample from the flask with the ascorbic acid solution was poured into a
different flask using a graduated cylinder.
8. 2-3 drops of acetic acid were dropped into the sample for the source of H+.
9. 2-3 drops of starch were added to the sample in the flask for color indication.
10. The flask with the ascorbic acid, acetic acid, and starch was placed under the buret for
titration.
11. Iodine was slowly titrated until the color changed.
12. Once the color changed, the volume on the buret and the color were recorded.
Experiment #2: Vitamin C Concentration in Orange Juice
1. Using a graduated cylinder, 20 mL of freshly squeezed orange juice was poured into a flask.
2. 30 mL of water was poured into the same flask for a total of 50 mL solution.
3. 2-3 drops of starch were added into the flask.
Name:
Date: 2/17/25
Experiment #: 4
Title: Molarity Vit C
Purpose:
The purpose of this experiment is to determine the concentration of ascorbic acid (vitamin C) in
oranges, lemons, and limes by using a titration mixture of iodine, starch, and ascorbic acid, by
reaching the endpoint and calculating the molarity.
Procedure:
Experiment #1: Vitamin C Concentration in Iodine
1. A sheet of weighing paper was placed on a balance and the balance was tared to 0 g.
2. 0.5 g of ascorbic acid was placed on the weighing paper and measured on the balance.
3. The ascorbic acid was placed into a volumetric flask,
4. 250 mL of water was added using a funnel into the volumetric flask.
5. The flask was swirled lightly and the ascorbic acid was dissolved.
6. A buret with 0.01 M solution of iodine was prepared for titration.
7. A 10 mL sample from the flask with the ascorbic acid solution was poured into a
different flask using a graduated cylinder.
8. 2-3 drops of acetic acid were dropped into the sample for the source of H+.
9. 2-3 drops of starch were added to the sample in the flask for color indication.
10. The flask with the ascorbic acid, acetic acid, and starch was placed under the buret for
titration.
11. Iodine was slowly titrated until the color changed.
12. Once the color changed, the volume on the buret and the color were recorded.
Experiment #2: Vitamin C Concentration in Orange Juice
1. Using a graduated cylinder, 20 mL of freshly squeezed orange juice was poured into a flask.
2. 30 mL of water was poured into the same flask for a total of 50 mL solution.
3. 2-3 drops of starch were added into the flask.
