Paper 1 October/November 2007 PHYSICS (0625/01) IGCSE
A substance can exist in three different states: solid, liquid or gas.
Each of the two statements below describes a change of state.
change 1 Molecules move closer together but continue to travel throughout the substance.
change 2 Molecules stop travelling throughout the substance and just vibrate about fixed positions.
Which changes of state do these statements describe?