Learning outcomes - after studying this topic, you should be able to:

• identify characteristics of physical states
• label phase diagrams and relate phase diagrams to changes in state with temperature and pressure
• explain the anomalous behaviour of water using its phase diagram
• define supercritical fluids and the behaviour of compounds above the critical point
• interpret simple two-component phase diagrams

• Chapter 7 (in Blackman, Bottle, Schmid, Mocerino and Wille, Chemistry, 3^rd Edition, 2015 (John Wiley))

• Phase transitions (in ChemWiki)
• Supercritical fluids (in ChemWiki)
• Phase changes (in Wikibooks General Chemistry)

The chemistry of snowflakes Description: Video showing how snowflakes form and grow Contributed by Adam Bridgeman

States of Matter Contributed by Adam Bridgeman

How to make liquid carbon dioxide Description: Under pressure, dry ice melts to give liquid carbon dioxide. It only sublimes at lower pressures Tags: phase diagrams Contributed by Adam Bridgeman

Supercritical carbon dioxide Description: At 31 'C, carbon dioxide becomes super critical if the pressure is very high. In the supercritical phase, it occupies space like a gas but flows like a liquid Tags: phase diagrams Contributed by Adam Bridgeman

Supercritical carbon dioxide (2) Description: Supercritical carbon dioxide being stirred like a liquid Tags: phase diagrams Contributed by Adam Bridgeman