[Campbell Biology P.96] Which of the following best explains the mechanism of evaporative c... | Practice Question
Which of the following best explains the mechanism of evaporative cooling and a factor that reduces its efficiency?
A: Evaporative cooling occurs when the 'hottest' molecules leave the liquid surface, and it is enhanced by high humidity.
B: Evaporative cooling happens because the remaining liquid's temperature decreases as molecules with the greatest kinetic energy depart, and it is less effective in high humidity.
C: Evaporative cooling occurs only at boiling temperatures and is unaffected by air humidity.
D: It involves the release of heat as water vapor condenses, a process that is more efficient in high humidity.
Explanation
Evaporative cooling works because the molecules with the highest kinetic energy the 'hottest' ones are the most likely to escape as gas, leaving behind cooler molecules. High humidity means there's already a high concentration of water vapor in the air, which inhibits further evaporation and thus reduces the efficiency of cooling.