Experiment 4 : Vitamin C (Result and Discussion)

RESULTS

Sample		Iodine Solution
		1st mL	2nd mL	Average
Ascorbic Acid		70.00	85.00	77.50
Chrysanthemum	Fresh flower	33.10	-	33.10
	Leaves	96.00	-	96.00
	Dry flower	61.00	-	61.00

Standard Calculation for conversion factor:

Volume of ascorbic acid                     =          Strained extract

77.50 mL                     =          1mg/ml vit C

Fresh Flower Extraction Calculation:

33.10 mL of iodine                             à        ? vit C

                                                            =          (1 mg/ mL ÷ 77.50 mL) × 33.10 mL

                                                            =          0.43 mg / mL vit C

Therefore, in 1 mL of fresh flower extraction has 0.43 mg of vitamin C

Leaves Extraction Calculation:

96.00 mL of iodine                             à        ? vit C

                                                            =          (1 mg/ mL ÷ 77.50 mL) × 96.00 mL

                                                            =          1.29 mg / mL vit C

Therefore, in 1 mL of fresh flower extraction has 1.29 mg of vitamin C

Dried Flower Extraction Calculation:

61.00 mL of iodine                             à        ? vit C

                                                            =          (1 mg/ mL ÷ 77.50 mL) × 61.00 mL

                                                            =          0.79 mg / mL vit C

Therefore, in 1 mL of fresh flower extraction has 0.79 mg of vitamin C

Discussions

          I2(aq) +     C6H8O6(aq)            -->       C6H6O6(aq)          + 2 H+(aq)         + 2 I-(aq)

         Iodine    Ascorbic acid(vitamin C)       Dehydroascorbic acid   Hydrogen ion   Iodide ion