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how your calculations for Trial 1 below. Molarity of standardized KIO, solution_

ID: 717676 • Letter: H

Question

how your calculations for Trial 1 below. Molarity of standardized KIO, solution_0.Ol COmo/L Trial Sample size, mL Final buret reading, mL 23.00 32.81 12.20 42.l Initial buret reading, m Total volume KIO, mL 1O. 3587.31 .s Moles KIO, mol Tlo les Vitamin C, mol m fHt2fft 42km Grams Vitamin C, g mg Vitamin C, mg Average mg of Vitamin C, mg Based on your average mass of Vitamin C in 25 mL of solution, how many milligrams of Vitamin 5.00 2,005,00 2S.0o .0 32.8 37.3S C would there be in 500 mL of solution? (Show your work) Compare your results above with the amount of Vitamin C in one packet of Emergen-C, which i mg. If your results vary, list some possible reasons for the difference.

Explanation / Answer

molarity of standardised KIO3=0.0100

principle involved: vitamin C contains ascorbic acid(C6H8O6)

reaction between ascorbic acid and potassium Iodate and ascorbic acid as fallows

KIO3 + 5KI + 6H+ 3I2 + 6K+ + 3H2O

C6H8O6 + I2 C6H6O6 + 2I- + 2H+

Based one above equations we can infer that one mole of ascorbic acid requires one mole of iodine, similarly one mole of iodine can be formed from 1/3 mole of KIO3

So totally one mole of ascorbic acid requires 1/3 mole of KIO3

ONE MOLE OF KIO3 = 3 MOLES OF VITAMIN C

MASS OF VITAMIN C = 176 X no of moles of ascorbic acid

trail

1

2

3

4

Sample size

25

25

25

25

Final burette reading

23

32.89

42.20

42.01

Initial burette reading

12.65

23

32.89

32.35

Toal volume of KIO3,ml

10.35

9.89

9.31

9.44

Moles of KIO3

0.0001035

0.0000989

0.0000931

0.0000944

Moles of vitamin C

3X0.0001035=0.0003105

3X0.0000989=0.0002967

3X0.0000931=0.0002793

3X0.0000944=0.0002832

Grams of vitamin C

0.054648

0.0522192

0.0491568

0.0498432

Mg of vitamin C

54.648

52.2192

49.1568

49.8432

trail

1

2

3

4

Sample size

25

25

25

25

Final burette reading

23

32.89

42.20

42.01

Initial burette reading

12.65

23

32.89

32.35

Toal volume of KIO3,ml

10.35

9.89

9.31

9.44

Moles of KIO3

0.0001035

0.0000989

0.0000931

0.0000944

Moles of vitamin C

3X0.0001035=0.0003105

3X0.0000989=0.0002967

3X0.0000931=0.0002793

3X0.0000944=0.0002832

Grams of vitamin C

0.054648

0.0522192

0.0491568

0.0498432

Mg of vitamin C

54.648

52.2192

49.1568

49.8432