When a liquid evaporates from an open container, the temperature of the remaining liquid decreases. Which statement best explains why this cooling occurs?
The molecules that escape carry away potential energy, causing the remaining molecules to lose mass.
The most energetic molecules escape from the liquid surface, leaving behind molecules with a lower average kinetic energy.
Escaping molecules collide with air molecules and are reflected back into the liquid at a lower speed.
The surface area of the liquid decreases, which directly reduces the thermal energy stored in the liquid.
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.