Atomic Spectra
Electrons need to absorb (take in) energy to move from
lower to higher energy levels.
Electrons need to emit (give off) energy to move from
higher to lower energy levels.
Atomic Spectra
Atomic spectra show the energy absorbed or emitted
by the electrons.
Each element has it’s own unique spectrum, which can
be used like a bar code to identify the atom.
An electron moves to an excited state when it absorbs a
photon of EM radiation that contains just the right
amount of energy needed to go from a lower energy
level to a higher energy level.
An electron moves to an excited state when it absorbs a
photon of EM radiation that contains just the right
amount of energy needed to go from a lower energy
level to a higher energy level.
An electron does not absorb EM
radiation that contains too little or
too much energy to go from one
energy level to another.
An electron moves to an excited state when it absorbs a
photon of EM radiation that contains just the right
amount of energy needed to go from a lower energy
level to a higher energy level.
An electron does not absorb EM
radiation that contains too little or
too much energy to go from one
energy level to another.
An electron in an excited state
quickly returns to its ground state.
It emits a photon that contains the
amount of energy the electron lost.
An electron can move to any available energy level in the
electron cloud skipping energy levels in between.
An electron can move to any available energy level in the
electron cloud skipping energy levels in between.
The diagram to the right shows
the various wavelengths of EM
radiation emitted as an
electron in a hydrogen atom
moves between the different
energy levels in the cloud.
An electron can move to any available energy level in the
electron cloud skipping energy levels in between.
The diagram to the right shows
the various wavelengths of EM
radiation emitted as an
electron in a hydrogen atom
moves between the different
energy levels in the cloud.
The photons that are emitted
create an atomic emission
spectrum.
Some, but not all, of the
emissions are visible light (400
nm to 700 nm).
Each element has its own unique emission spectrum
because no two elements’ electrons are arranged the
same way in the electron cloud.