Spectroscopy

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Spectroscopy

• What it is and some practical applications

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Spectroscopy

• the science of having to do with the
  _______________________________ of
  spectra.
• ________________- the band of colors formed when
  any form of radiant energy is broken up.

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Some practical uses

• There are several forms of spectroscopy used in
  ____________________________________
• __________________- identification of material in
  the source of light.
• ____________________ earth observation, weather
  monitoring, ultrasound
• ______________________ MRIs, X-rays, etc

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Energythink EMR

• _____________________________ a series of energy
  waves that travel in a vacuum at 3.00 x 1010
  cm/s. This includes (from low to high) radio,
  radar, micro, IR, visible, UV, X-ray, gamma rays,
  and cosmic rays.

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Electromagnetic spectrum
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The Anatomy of a Wave

• __________________- wave height from origin to
  crest.
• ___________________(?)- distance between a crest
  to the next crest or a trough to the next
  trough.
• __________________(?) the number of wave cycles
  to pass a given point per unit time. (usually
  considered cycles per second)
• ________ (Hz)- the SI unit for frequency. Cycles
  per second, 1/s or 1 s-1 where cycles are left
  unwritten but understood.

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Origin

Amplitude
Frequency
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Atomic emission spectrum

• Atomic emission spectrum- the ___________
  ________________ obtained by passing light
  through a prism (the light is emitted by atoms of
  an element in the gaseous state). The spectrum
  emitted is unique to that element. gtdischarge
  tubeslt

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What colors/lines do you see

• visibly?

• with the spectra sheet?

• ________________________________________
• ________________________________________
• ________________________________________
• ________________________________________
• ________________________________________
• ________________________________________

• ________________________________________
• ________________________________________
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• ________________________________________
• ________________________________________

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• Electrons passing through a gas discharge tube
  _____________________________
• Excited atoms ____________ when the electrons
  return to the ________________.
• ________________________ emitted depend on the
  energies of the ________________ of the electrons
  (in the visible spectrum you would observe ______
  ____________).

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Some spectra types
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The discovery of an element

• In 1868, _________ ________ observed bright
  emission lines from a spectroscope adapted to fit
  his telescope.

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Unknown element

• Testing took place at the College of Chemistry in
  London.
• _______________ _______________ _______________
  _______________ _______________

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The spectrum of the star Procyon, wrapped around
row after row from left to right and top to
bottom across the visible spectrum from red to
blue, shows a myriad of dark lines caused by the
absorption of light in the hot star's cooler
atmosphere.
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The Horsehead Nebula
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(No Transcript)
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Helium shortages

• Main Uses of He
• Super cooling of ___________
• Laser _________
• _____________ (only about 8 of the market)

• The helium producing captial of the world is in
  __________________
• If consumption rates continue without _____
  ___________________ sources, it is estimated that
  our federal reserves ___________
  __________________.

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Satellite Images in visible wavelengths
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Visible (vis) Infrared (IR)
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Visible Light
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Visible light