Materials

  • 4x 50 mL tube
  • 1000 mg Vitamin C tablet (you can also use two 500mg of course)
  • Plastic bag
  • Iodine (2%) availabe at a drug store
  • Hydrogen peroxide (3%) also from a drug store
  • Liquid Starch Solution (0.3%, so 3 grams of starch in 1 liter of heated water)
  • Safety goggles

Method

  1. Put on those safety goggles
  2. Crush the Vitamin C tablet in a plastic bag
  3. Put the powder in a 50 mL tube, label it with “Reagent A”
  4. Add 50 mL of warm water. Stir or shake for at least 30 seconds. (
  5. Transfer 5 ml of Reagent A into a new 50 mL tube, label as “Reagent B”
  6. Add 40 mL of warm water and 5 mL of the iodine.
  7. In the third 50 mL tube mix 15 mL of warm water, 15 mL of the hydrogen peroxide and 2.5 mL of the liquid starch. This is “Reagent C”
  8. Mix 25 mL of Reagent C with 25 mL of Reagent B
  9. Immediately place in a spectrometer or just watch what happens
  10. Record the change to the spectrum

Somewhere between a few seconds and a few minutes, the liquid will suddenly turn dark blue.

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