Practise explaining how temperature, surface area and moving air affect evaporation through particle escape and reduced return with CAIE IGCSE Physics questions and mark schemes.
Three identical dishes, A, B and C, contain an equal volume of water.
Dish A is outside in sunlight and experiences no wind during the day. Dish B is outside in sunlight and experiences a strong wind during the day. Dish C is in a dark room.
Water evaporates from each dish. After 12 hours, a student measures the volume of water in each dish. Dish C contains the largest volume of water and dish B contains the smallest volume of water.
Explain, in terms of particles, why the three dishes have different volumes of water.
energy from the Sun transfers to / is absorbed by (water) molecules, (so KE of (water) molecules increases)
molecules with high(er) energy / KE / fast(er) moving molecules escape (from the surface)
wind removes molecules when they have left the surface (so they do not re-enter the liquid)
any one from:
- wind increases the rate of evaporation
- (absorption of) energy from the Sun increases the rate of evaporation
- least/less water evaporates/lower rate of evaporation from dish C
- most/more water evaporates/ higher rate of evaporation from dish B