Racing Raisins
What you need one package of raisins a large beaker (800ml) carbonated water stop clock
What to do participants are invited to choose a raisin to drop into a large beaker of carbonated water time how quickly the raisin sinks and rises back to the surface participants are required to race with each other observe the bubbles forming on the food surface during the experiment
What to do prizes are awarded to the top three fastest times special prizes will be given to participants who enable to explain the scientific reason behind
What is happening a raisin is denser than water so it will initially sink carbonated water contains carbon dioxide bubbles rough surface creates a large surface area for the bubbles to attach to the number of bubbles increases on the raisin, raisin and bubbles become less dense than water, and rise to the surface
What is happening once it has risen to the surface, the bubbles burst, releasing the carbon dioxide into the air raisin sinks again therefore, the items that work best will have a density that is only slightly greater than that of water