Gas and Pressure
These downloadable videos and animations are part of the multimedia package Stuff and Substance, developed by the Gatsby Science Enhancement Programme (SEP). They can be used to develop the ideas relating to the pressure of the gas state and dependence of the boiling point on external pressure.
The pressure of a substance in the gas state is due to bombardment by the particles, and depends on how many collisions take place at once (the concentration of particles) and how hard the collisions are (the energies of the particles which depends on the temperature of the sample). The animations can be used to develop these ideas. A further animation (in conjunction with other diagrams in Stuff and Substance) can be used to explain why boiling point depends on the external pressure. The two videos re-visit experiments met earlier in Stuff and Substance and can be used to consider the role of atmospheric pressure in the observations.
These video and animation files form part of the resources in the section Gas and Pressure in the Stuff and Substance multimedia package, which provides a series of interactive pages that can be used by teachers or students in the classroom.