During the process of evaporation, some molecules escape from a liquid. Which molecules are able to escape, and what is the resulting effect on the average kinetic energy of the remaining molecules?
Molecules escaping: those with the lowest kinetic energy; Average kinetic energy of remaining molecules: decreases
Molecules escaping: those with the lowest kinetic energy; Average kinetic energy of remaining molecules: increases
Molecules escaping: those with the highest kinetic energy; Average kinetic energy of remaining molecules: decreases
Molecules escaping: those with the highest kinetic energy; Average kinetic energy of remaining molecules: increases
528 exam-style questions on CIE IGCSE Physics 2.2 Thermal properties and temperature, covering 2.2.1 Thermal expansion of solids, liquids and gases, 2.2.2a Internal energy and temperature, 2.2.2b Specific heat capacity, 2.2.3a Melting, boiling, condensation and solidification, 2.2.3b Evaporation, and 2.2.3c Cooling by evaporation. Each one has a worked solution and a mark scheme showing where the marks go.