Factors Affecting Evaporation

Factors Affecting Evaporation
Nature Of Liquid
Motion Of Air
Example: Drying your hair with a hair dryer,
The moving air from the hair dryer removes the
molecules of liquids as soon as they escape
from the surface of your hair.
You cool faster in moving air than still
air
Humidity Of Surrounding Air
Example: Wet clothes do not dry easily when air
is damp and skin feels dry in airconditioned
room.
Area of Exposed Area
Temperature
Evaporation can occur at any temperature
Increase in temperature = increase in rate of
evaporation
Warmer liquid
Greater number of molecules at the surface
layer are energetic enough to escape
The rate of evaporation increases
when there is more exposed surface
area
Evaporation only takes place at
the exposed surface area of a
liquid
The larger the exposed surface area, the
more molecules can escape from the
liquid
Rate of evaporation decreases with
increasing humidity and increases with lower
humidity.
Example: Mercury hardly evaporates at room
temperature as it has a boiling point of 357
degrees Celsius.
Rate of evaporation is faster with moving air
present
Liquids with a lower boiling point
evaporate faster
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