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Video: Impress Your Friends With This Amazing Chemistry Trick That Seems Magical

It's called the iodine clock reaction, and all it takes is a few simple household chemicals you may already have. The speed of the transformation is stunning.

You are going to be surprised at how quickly this chemical reaction takes place. Watch what happens when you add two colorless liquids together in a glass or beaker.

The video below shows the astonishingly immediate chemistry trick that transforms the appearance of the contents in your glass in a split second. 

TikTok user @engineeredlabs treats us to a presentation of the experiment.

Fascinating, isn't it? 

There is an at-home version of this that you can do yourself. Here is all you need:

  • Distilled water (tap water will work as well)
  • A couple plastic cups
  • 1000 mg vitamin C tablets
  • Tincture of iodine (2%)
  • Hydrogen peroxide (3%)
  • Liquid laundry starch

Imagination Station provides the list of what to do:

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  1. Make a vitamin C solution by crushing a 1000 mg vitamin C tablet and dissolving it in 2 oz. of water. Label this as "Vitamin C stock solution."
  2. Combine 1 tsp of the vitamin C stock solution with 1 tsp of iodine and 2 oz. of water. Label this "Solution A."
  3. Prepare "solution B" by adding 2 oz. of water to 3 tsp of hydrogen peroxide and 1/2 tsp of liquid starch solution.
  4. Pour solution A into solution B, and pour the resulting solution back into the empty cup to mix them thoroughly. Keep pouring the liquid back and fourth between the cups.

Quoting directly from Imagination Station, this is what is going on:

"There are actually two chemical reactions going on at the same time when you combine the solutions. During these reactions two forms of iodine are created—the elemental form and the ion form."

Again, here is Imagination Station explaining further:

  1. In Reaction # 1 iodide ions react with hydrogen peroxide to produce iodine element which is blue in the presence of starch. BUT, before that can actually happen, the Vitamin C quickly reacts and consumes the elemental iodine. 
  2. The net result, at least for part of the time is that the solution remains colorless with excess of iodide ions being present. Now after a short time as the reactions keep proceeding in this fashion, the Vitamin C gets gradually used up. Once the Vitamin C is used up, the solution turns blue, because now the iodine element and starch are present.

A couple notes: The iodine stains, so wear rubber gloves and be careful not to spill when conducting the experiment. You can get rid of the liquids by pouring them down a drain, but be sure to use plenty of water.

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