An absorption spectrum occurs when a photon is absorbed, exciting an electron to a higher quantum energy state. Absorption spectra involve atoms increasing in energy level. An emission spectrum occurs when a photon is emitted as an electron drops to a lower quantum energy state, with emission spectra involving electrons decreasing their energy level. The document also provides a conversion between electronvolts (eV) and joules (J).

1. Absorption Spectrum
Photon is
absorbed
and excites
electron to
higher
quantum
energy
state.
0 eV
-10 eV
hf
Ground state
ΔE

2. Absorption Spectrum
Absorption
spectra
always
involve
atoms going
up in
energy
level.
0 eV
-10 eV
ionized

3. Emission Spectrum
Photon is
emitted
and
electron
drops to
lower
quantum
energy
state.
0 eV
-10 eV
hf
Excited state
DE

4. Emission Spectrum
Emission
spectra
always
involve
electrons
going down
in energy
level.
0 eV
-10 eV
ionized

5. Converting eV to Joules (J)
1 eV
= 1.602 x 10-19J