How Does Temperature Affect the Rate of Evaporation?

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Increased temperatures accelerate the rate of evaporation, while decreased temperatures slow down the process. First of all, heating of the liquid energizes the molecules, allowing them to escape and move into the air. Second, heat in the nearby atmosphere increases evaporation because warmer air is able to hold more water vapor.

Evaporation, a necessary component of the Earth’s water cycle, takes place when a substance changes states of matter from a liquid into a gas. Several factors affect the rate of evaporation, and temperature is one of the major ones. With an increase in temperature, a direct increase in kinetic energy at the surface of the liquid takes place. The molecules in the liquid begin to move faster, colliding with one another at an increasing rate until some of the molecules escape into the atmosphere as water vapor. Other factors affecting evaporation rate include humidity, the nature of the liquid, the amount of wind present and the surface area of the liquid. Conditions that speed the rate of evaporation, in addition to higher temperature, include an increase in wind, an increase in surface area and a decrease in humidity. Ideal conditions for evaporation include dry hot air surrounding a hot liquid with a large surface area.