MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Bromine gas diffusion. Bromine vapour (orange) filling two gas jars as a demonstration of gas diffusion. Initially, the gas only filled the bottom gas jar. Because gas molecules can move independently of each other and do so randomly, a gas spreads out from its source in a process called diffusion. The diffusion rate depends mainly on the temperature and the medium through which the diffusion takes place. In this case, the medium is air. The gas colour allows the diffusion to be observed. For the start of the experiment, see image C011/4509.
Model release not required. Property release not required.