Name: Ashley N. C.
Status: student
Age: 15
Location: N/A
Country: N/A
Date: 2000-2001
Question:
Are there any other organisms besides fireflies that need the
chemical bioluminescence? And how can a chemical reaction that gives off light
occur without absorbing or producing heat?
Replies:
Certain species of shrimp and other sea creatures emit visible light. A
chemical reaction that produces a product in an excited electronic state
whose energy differs from either the ground electronic state or some
intermediate electronic state by an energy difference is E2-E1=hc/(lambda)
where h is Planck's constant, c is the speed of light in a vacuum and
(lambda) is a wave length between 400 and 700 nanometers can emit visible
light without the generation of much, if any, heat. It's the difference in
the excited and lower electronic states that counts.
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