Transcript Atomic Emission Spectra

Atomic Emission Spectra
Electromagnetic Spectrum
Visible Spectrum
White light (such as the light produced by
the sun) is actually made up of 7 individual
colors of light.
ROYGBIV-Red, Orange, Yellow, Green,
Blue, Indigo, and Violet –are the colors of
the visible spectrum
The visible spectrum are the wavelengths
of light that the eye can see
Atoms and Energy
When an atom is exposed to energy (heat, light,
electricity, laser energy, etc), the electrons in the atom
absorb the energy and move to a higher energy level.
These electrons are said to be in the excited state.
The excited electrons return to their stable lower energy
state (ground state) by releasing the energy that was
absorbed.
The energy that is released is seen as a specific color of
light.
The color that is seen is based on the atom’s electron
arrangement and the wavelengths of light being emitted.
Examples observed in everyday life: neon signs,
fireworks, logs that give off colored flames, highway
lights
Atomic Emission Spectra
If the light that is emitted as electrons return to
their ground state is passed through a prism, the
light is separated into its individual components.
The atomic emission spectrum of an atom is the
set of wavelengths of the light emitted by
electrons of the atom.
Each element’s atomic emission spectrum is
unique and can be used to identify an element,
much like a fingerprint can be used to identify a
person.
A flame test is a laboratory procedure that can
be used to identify an unknown element.
Emission Spectrum
Hydrogen
Helium
Mercury
Uranium
Emission Spectrum