During the operation of a cryogenic storage vessel, liquid nitrogen at 77 K vaporises into nitrogen gas at 77 K under constant atmospheric pressure.
Which statement correctly describes the change in the average kinetic energy and the total intermolecular potential energy of the nitrogen molecules during this vaporisation process?
Both the average kinetic energy and the potential energy of the molecules increase.
The average kinetic energy of the molecules increases, while their potential energy remains constant.
The average kinetic energy of the molecules remains constant, while their potential energy increases.
The average kinetic energy of the molecules remains constant, while their potential energy decreases.
56 exam-style questions on OCR A A Level Physics Thermal physics, covering Temperature, Solid, liquid and gas, Thermal properties of materials, and Ideal gases. Each one has a worked solution and a mark scheme showing where the marks go.