Smoke From Your Fingertips This time, a little magic! You'll need a book of safety matches. Tear off the striking surface from the book of paper matches. Put it in a tinfoil-lined bowl, cardboard side up. Light the cardboard and let it burn completely. After it has burned, there should be a reddish residue left behind. Let it cool. Wipe your fingertip and thumb on the residue. When you now rub your fingertip and thumb together, you should get smoke. The residue contains red phosphorus, which oxidizes at the low temperature caused by the friction between your thumb and finger. It won't burn you. This is an old magician's trick. If you do this in the dark, you will see an eerie greenish glow. Dr. Deadly's Science Lab Question "Did you notice the word 'oxidizes' above? What does it mean? Give some other examples." Scroll way down to check your answer. 'Oxidize' means 'combine with oxygen', usually slowly. Metal containing iron does this when it rusts. Fat turns rancid after prolonged exposure to air. Science Lab | Resources