States of Matter and Gas Pressure — OCR GCSE Combined Science B J260
OCR GCSE Combined Science B · J260
States of Matter and Gas Pressure
What you need to know
Explain the differences in density between the different states of matter based on the arrangements of their atoms or molecules.
Describe, using the particle model of matter, how mass is conserved when a substance melts, freezes, evaporates, condenses or sublimates.
Understand that physical changes of state differ from chemical changes, and that a material recovers its original properties if a physical change is reversed.
Use the particle model to describe how heating a system changes the stored energy, thereby raising its temperature or producing changes of state.
Explain how the motion of molecules in a gas relates to both its temperature and pressure, and establish the qualitative relationship between gas temperature and pressure at a constant volume.
