Flourescence of Chlorophyll Flashcards
What happens when chloropyll and other pigments absorb photons?
THe colors corresponding to the absorbed wavelengths disappear from the spectrum of the transmitted and reflected light, but energy cannot disappear.
WHen a molecule absorbs a photon, one of the molecule’s electrons is
elevated to an orbital where it has more potential energy.
WHen the electron is in its normal orbital, the pigment molecule is said to be
in its ground state
after absorption of a photon boosts an electron to an orbital of higher energy, the pigment molecule is said to be in
an excited state
THe only photons absorbed are those whose energy
is exactly equal to the energy between the ground state and the excited state and this energy varies from one kind of atom or molecule to another.
A particular compound absorbs only photons corresponding to
specific wavelengths which is why each pigment has a unique absorption spectrum.
the energy of an absorbed proton is converted to the
potential energy of an electron raised from the ground state to an excited state
how long can an electron remain in an excited state
not long, high energy states are unstable
generally, when pigments absorb light, their excited electrons
drop back down to the ground state orbital in a billionth of a second releasing their excess energy as heat
some pigments including chlorophyll emit
light as well as heat after absorbing protons
The electron jumos to a state od greater energy as it falls back to
ground state and a photon is given off. This is known as afterglow (?)
afterglow is called
flourescence
Flourescence has a longer wavelength and hence
less energy than the light that excited the pigment.
If a solution of chlorophyll isolated from chloroplasts is illuminated it will fluoresce in what part of the spectrum and also give off heat
????
distinguish between light and dark reactions
???
