States of Matter – Solid, Liquid, Gas and Beyond

An ice cube melting in a glass of water quietly demonstrates one of the most fundamental ideas in all of physics and chemistry: matter changing between states as the balance between molecular attraction and molecular energy shifts. This episode explains solids, liquids and gases at the molecular level, why phase changes absorb or release hidden latent heat, why boiling point depends on pressure, and what lies beyond the familiar three states — plasma, supercritical fluids and the exotic Bose–Einstein condensate.

You'll come away understanding what actually distinguishes a solid from a liquid from a gas, why a boiling pot of water stops rising in temperature, why water boils at a lower temperature on a mountaintop, what a supercritical fluid is, why plasma is really the universe's most common state of matter, and what a Bose–Einstein condensate reveals about the strange edges of quantum physics.

Talking Science is sponsored by Kinsoft. Visit www.kinsoft.com.au

Further reading: NIST – background on the 1995 Bose–Einstein condensate experiments and the 2001 Nobel Prize in Physics; Royal Society of Chemistry – resources on states of matter and phase changes; Scientific American – features on plasma physics and supercritical fluids.