ANDREW MCCLENAGHAN / SCIENCE PHOTO LIBRARY ANDREW MCCLENAGHAN / SCIENCE PHOTO LIBRARY
Experiment to illustrate diffusion of a gas. Two gas jars are arranged with their open ends together, but their contents are kept separate by a glass lid. The lower gas-jar is filled with gaseous bromine (brown); the upper jar contains air (apparatus on left). When the lid is removed, diffusion causes the gases to mix, and bromine can be seen gradually rising into the upper jar (apparatus on right).
Model release not required. Property release not required.