The purpose of this easy experiment is to determine how the buoyancy of a substance can be changed.
Things Required:
Drinking glass
Club soda
Modelling clay
Directions:
Fill the drinking glass three-quarters full with soda. Immediately, add 5 tiny balls of clay one at a time. The clay pieces must be about the size of a rice grain. Wait and watch.
This Is What Happens:
Bubbles collect on the clay. The clay pieces rise to the surface, spin over, and fall to the bottom of the glass, where more bubbles start to stick to them again.
Science Behind It:
The soda contains carbon dioxide, which forms bubbles that stick to the clay. The clay balls initially sink because their weight is greater than the upward buoyant force. The gas bubbles act like tiny balloons that make the balls light enough to float to the surface. The carbon dioxide bubbles are knocked off at the surface, and the balls again sink to the bottom until more bubbles stick to them.
