Today the 5th and 6th grade classes explored the changes that occur between the different forms, or states, of matter. Matter can transition between solid, liquid and gas states by adding or removing energy in the form of heat. We also explored how pressure can affect temperature and the state of matter. We all know that when a liquid transitions to a gas, it is called vaporization (or evaporation), and changes between solids and liquids are referred to as melting and freezing, but some of the change terms were new, such as deposition (gas to solid). The snow began to fall outside during class allowing the students to see deposition in action! Through demonstrations with dry ice (the solid state of carbon dioxide), the students were able to observe one particularly exciting transition in action: sublimation (solid to gas).
After comparing regular “wet” ice to dry ice, we studied sublimation by adding dry ice to water. The warmth of the water causes the solid dry ice to sublimate rapidly, releasing clouds of white vapor (carbon dioxide gas) that quickly sinks and dissipates. This was great fun to investigate and allowed the students to see all three states of matter (solid, liquid and gas) in a single cup! The most exciting part was when Dr. G applied a film of soap to the top of the dry ice cup, allowing a large bubble to form filled with the white carbon dioxide gas!
Check out this video on how to make dry ice bubbles!