Cloud in a Bottle

We create a cloud in a bottle using warm water and smoke. Some warm water is placed in a plastic bottle and then some smoke is drawn in using a glowing splint. The bottle is sealed and then squeezed and released. The change in pressure causes the water vapour inside to condense on the smoke particles, forming a cloud. Physics - Energy And Radioactivity - Learning Points. Warm water will give off water vapour. If water vapour is cooled it will condense. Rapid cooling can convert water vapour to fine droplets, but this process is speeded up if particles are in the vapour/air mix that can cause nucleation. Cloud seeding is the artificial nucleation of clouds using a common chemical called silver iodide. Cloud seeding can be used to create rain in arid areas, but it is very expensive and not always successful. A Twig Experiment Film. Let students experience real experiments in lab conditions anywhere, from setup, method all the way through to analysis and real-world application.