Absorption SpectrumPhoton is absorbed and excites electron to higher quantum energy state.

0 eV

-10 eV

hf

Ground state

ΔE

Absorption SpectrumAbsorption spectra always involve atoms going up in energy level.

0 eV

-10 eV

ionized

Emission SpectrumPhoton is emitted and electron drops to lower quantum energy state.

0 eV

-10 eV

hf

Excited state

DE

Emission SpectrumEmission spectra always involve electrons going down in energy level.

0 eV

-10 eV

ionized

Converting eV to Joules (J)

1 eV = 1.602 x 10-19J