Observations and results
After water was added to the drawing, did the ink stay in place? Whereas after isopropyl alcohol was added, did the ink run and spread out, creating colorful artwork?
The ink used in permanent markers does not dissolve in water, meaning the ink is water insoluble. This is why when you added drops of water to the designs you made on the T-shirt, the ink should have pretty much stayed in place. Permanent marker ink, however, does dissolve in isopropyl alcohol, meaning the ink is soluble in it. Because of this, when you added drops of alcohol to the designs on the T-shirt, the ink should have spread out and ran along the fabric with the alcohol, creating a circle full of color. (This is similar to what happens when a drop of water lands on a piece of paper with something printed on it, and the ink starts to run on the paper, making the text blurry.) If you let the design that you put water drops on dry, dripping alcohol on it should make the ink run and create another colorful design on your T-shirt!
More to explore
Solutions as Special Mixtures, from Thunderbolt Kids
Paper Chromatography: Is Black Ink Really Black?, from Science Buddies
Sharpie Marker Tie Dye T-Shirts, from Pintriedit
Solubility Basics—What is Solubility, from Solubility of Things
Science Activities for All Ages!, from Science Buddies
This activity brought to you in partnership with Science Buddies