During a marathon, a runner's body is cooled by the evaporation of sweat from their skin.
Which molecules escape from the liquid sweat during evaporation, and what happens to the average kinetic energy of the remaining sweat molecules?
Escaping molecules: the ones with higher kinetic energy; Average kinetic energy of remaining molecules: decreases
Escaping molecules: the ones with higher kinetic energy; Average kinetic energy of remaining molecules: increases
Escaping molecules: the ones with lower kinetic energy; Average kinetic energy of remaining molecules: decreases
Escaping molecules: the ones with lower kinetic energy; Average kinetic energy of remaining molecules: increases
313 exam-style questions on CIE IGCSE Physics 2.2.3a Melting, boiling, condensation and solidification. Each one has a worked solution and a mark scheme showing where the marks go.