Sugar–Water Fiber Optics

Practice this demonstration before performing to determine the best quantity of water to use for different balloon sizes. Also, practice placing the balloon over the flame to make it appear as if the two balloons are identical. Do not make it obvious that you are placing the water-filled balloon over the flame at a “specific” location on the balloon. Students may quickly question whether there is something in the balloon that prevents it from popping.|Do not use a Bunsen burner or propane burner for this demonstration. The flame will be too large and hot and will quickly pop the balloon containing water.|Thick, opaque, colored balloons work best because the water inside the balloon will not be visible.