Prelab for Determination of Vitamin C by Redox Titration SD Flashcards


Set Details Share
created 4 weeks ago by BerryJamJam
3 views
50 / 50 - 100 %
Subjects:
general chemistry ii lab
show moreless
Page to share:
Embed this setcancel
COPY
code changes based on your size selection
Size:
X
Show:

1

In this experiment, iodine is

  • oxidized to I- (I 1 minus)
  • oxidized to IO3 - (I O3 1 minus)
  • reduced to I- (I 1 minus)
  • oxidized to IO- (I O 1 minus)
  • reduced to IO3 - (I O3 1 minus)
  • reduced to IO- (I O 1 minus)

reduced to I- (I 1 minus)

2

In this experiment, what reacts with the starch to turn it purple?

  • excess dehydroascorbic acid.
  • excess iodine.
  • excess iodide ion.
  • excess ascorbic acid.

excess iodine.

3

In the balanced redox reaction between I2 and ascorbic acid, which of the following is true?

  • 1 mole I2 reacts with 1 mole ascorbic acid
  • 2 mole I2 reacts with 1 mole ascorbic acid
  • 3 mole I2 reacts with 1 mole ascorbic acid
  • 1 mole I2 reacts with 3 mole ascorbic acid
  • 1 mole I2 reacts with 2 mole ascorbic acid

1 mole I2 reacts with 1 mole ascorbic acid

4

How many moles of ascorbic acid can be reacted with 0.00013 moles of I2 in this experiment?

0.00013 moles

5

A redox titration similar to this one requires 30.65 mL of iodine solution to titrate a sample containing 25.00 mL of 0.0002487 M ascorbic acid to the end point. What is the molarity of the iodine?

  • 0.0002029 M
  • 0.2029 M
  • 0.2487 M
  • 0.0003049 M
  • 0.0002487 M
  • 0.3049 M

0.0002029 M

Ex.

Masc x Vasc = MI2 x VI2

MI2 = (0.0002487 x 25 ) / (30.65)

MI2 = 0.0002029 M