See 2 video demonstrations of diffusion in action. The first video shows a drop of food coloring diffusing through water. It is a video that is time lapsed at 1 frame/15 seconds. The second video shows a Ziploc bag of iodine placed into a beaker of starch water. It is a video that is time lapsed at 1 frame/30 seconds. The iodine diffuses out of the bag and into the starch water. Where the iodine is diffusing the starch water turns a dark blue.
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