The "Will Coke Dissolve a Nail?" experiment seeks to answer whether one of the active ingredients in Coca-Cola, phosphoric acid, can dissolve a nail. The experiment needs four to five different sodas, including Coca-Cola, as well as tap water, clear cups to keep the liquid in, steel nails and human toenail clippings. The student pours the various beverages into the cups, pouring enough liquid to cover the nails. The nails are then placed in the cups. The student then observes the experiment every 24 hours for four days. The physical characteristics of both the nail and liquid are recorded. After four days, the student concludes whether Coca-Cola, or any of the beverages, can dissolve a nail.
The experiment "The Density of Coca-Cola" explores whether Coca-Cola and Diet Coke will sink or float. The experiment requires two clear containers filled with tap water and a can of Coca-Cola and Diet Coke. The student pours the can of Coca-Cola into one container and the Diet Coke into the other. The conclusion is drawn after the student observes whether the soda sits on the top of the water or sinks to the bottom.
The "Coca-Cola Egg" experiment demonstrates the effects of Coca-Cola on teeth and answers the question "Does toothpaste really work?" The student places two eggs in two different glasses. Then, the student pours Coca-Cola over the eggs and lets them soak for 30 minutes. At the end of the 30 minutes, the student takes the eggs out of the soda and records observations about the appearance of the egg. After recording any observations, the student attempts to remove the discoloration from the egg using toothpaste. At the end of the experiment, the student answers the question "Does toothpaste really work?"
A simple Coca-Cola science fair project is to determine if Coca-Cola can clean a penny. In this experiment the student places a dirty penny in a cup of Coca-Cola. She leaves the cup alone for 24 hours and observes what happens to the penny, which will be completely cleaned. An extension of this science fair project is to leave the penny in the Coca-Cola for ten days. After the ten days, the student will find that the penny completely disappears.