Ask A Scientist© Physics Archive

Question:  Does the color of water effect the evaporation?
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Answer:  Well, water itself is colorless, so colored water must have had
some other kinds of molecules added to it.  Since evaporation happens
at the molecular level (individual molecules leave the surface)
only two things matter: the temperature, and the amount of surface
area available for the water to evaporate from.  Some additives
to water may have special effects at the surface (for example adding
oil leaves a film of oil on top of the surface, making it impossible
for water to evaporate).  And colored additives may change the
rate at which the water absorbs or releases heat, thus modifying
the temperature.  But other than that, color alone should have
no effect.
Arthur Smith
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