10. How We Use EM Spectrum for Spectroscopy

Give a summary of atomic spectroscopy

Movement of electrons from low to high energy levels (or vice versa) cause spectroscopic excitations

What can spectroscopic excitations be used for?

To work out energy gaps between subshells and orbitals

How can atomic spectroscopy be carried out?

Absorption and Emission

What does absorption spectroscopy do?

Measures light energy absorbed

How is absorption spectroscopy carried out?

Beam of white light passes through gaseous sample of element, photons of certain energy may be absorbed by atom causing electron to move from lower to higher energy level while the remaining light emerges at a lower intensity.

What does absorption spectroscopy looked like?

When light is examined by spectrometer, electronic transitions appear as dark lines against bright background

What does this mean (following off how absorption spectroscopy is carried out)?

This means that light of a frequency corresponding to energy of photon will be removed

What does emission spectroscopy do?

Measures light emitted

Describe how emission spectroscopy is the opposite to absorption spectroscopy?

Measures frequency emitted when excited electron falls to ground state when energy source removed