A laboratory cooling unit removes energy from a sample of substance R at a constant rate and constant pressure. The substance condenses and later freezes. Its temperature remains constant for 8 minutes during condensation and for 3 minutes during freezing.
Which statement gives the reason why the temperature of R stays constant for longer during condensation than during freezing?
The particles lose all of their kinetic energy during condensation but keep some kinetic energy while the liquid freezes.
The empty spaces between the gas particles must also be cooled during condensation before a liquid can form.
Forming the regular pattern during freezing uses up part of the energy released, so less energy reaches the cooling unit.
More energy is released as attractions pull widely spaced gas particles together than as touching liquid particles become fixed.
93 exam-style questions on OCR GCSE Chemistry 1.1 The particle model, covering 1.1.1 The particle model and changes of state and 1.1.2 Limitations of the particle model. Each one has a worked solution and a mark scheme showing where the marks go.