Activity 5 Vitamin C CeH0 is an essential nutrient found in

Activity 5: Vitamin C (CeH0) is an essential nutrient found in citric fruits and peppers, a other foods. A titration can be used to determine the concentration of vitamin C in foods. lodine is often used as the titrant. The balanced equation for this reaction is CeHsO6 (aq) + 12 (aq) Ch406 (aq) + 2p. (aq) + 2 H\'. (aq) Which has more vitamin C, a red bell pepper or an orange? To determine this, one could use a 0.0012 M iodine solution to titrate the juice extracted from each. The following table includes data from such an experiment. Use this data to calculate whether a red bell pepper or an orange contains more vitamin C. Record your results in the table below. a. Orange 175 5.0 0.0 6.2 Red Bell Pepper 130 5.0 6.2 14.8 Volume of juice extracted (mL) Amount of juice titrated (mL) Initial volume of I2 (mL) Final volume of 12 (mL) Volume of l2 solution used (mL) Volume of 12 solution used (L) Amount of 12 solution added (mol) Amount of Vitamin C (mol Mass of Vitamin C (mg) Concentration of Vitamin C in juice (mg/mL) Mass of Vitamin C in each fruit (mg) b. According to your calculations, which has more Vitamin C, orange juice or red bell pepper juice? Does this surprise you?

Solution

To calculate the total volume of I2 required = final volume-initial volume

Number of moles of I2 = volume in L * strength of I2 solution

Moles of I2 = moles of Vit-C

mass of vit -C = moles of vit-C * Molar mass of Vit-C (176.12g/mol)

concentration of vit c (mg/mL) = mass of Vit-C / 5mL

amount of vit-c in the fruit = mass/mL * volume of juice extracted

	Orange	Red bell pepper
Volume of juice extracted	175	130
Amount of juice used for titration (mL)	5	5
Initial volume of I2 (mL)	0	6.2
Final volume of I2 (mL)	6.2	14.8
Volume of I2 used (mL)	6.2	8.6
Volume of I2 used (L)	0.0062	0.0086
amount of I2 solution added (mol)	0.00000744	0.00001032
amount of Vit C(mol)	0.00000744	0.00001032
amount of vit-C (mg)	1.3103328	1.8175584
Concentation of Vit-C(mg/mL)	0.26206656	0.36351168
mass of Vit-C is each fruit (mg)	45.861648	47.2565184