1. Quantized Energy and Light
11/13/13

2. Quantized Energy
Bohr (chemist that created the atom model with orbitting electrons) determined that electrons have particular energy values
Electrons can only exist at a given “quantized” energy level
Quantum= the energy difference between certain orbital energies

3. Heisenberg Uncertainty Principle
Heisenberg said that it is impossible to know the exact location and energy of a given electron
Electrons are constantly moving, and are not always found at the energy level they started at
We only know the “probability” of finding an electron somewhere

4. Electron States Lowest possible energy level is “ground state”
Electron gains energy & moves to an “excited state”
Energy in the form of light is emitted when an electron loses energy & falls to a lower level

6. Light Creation An atom absorbs a “quantum” (certain amount of energy
The electron becomes “excited” (goes up 1 or more energy levels, leaving a hole in its orbital)
The electron loses energy as it “relaxes” (falls to a lower energy)
Light is emitted as it relaxes

7. Colors of Light
Different colors correspond to electrons relaxing shorter or longer distances
Falling farther=more energy emitted
Lower
Energy
High
Energy

8. “Invisible” Light
Some energies emitted during relaxation can’t be detected by our eyes
Ex) infrared, radio, ultraviolet, xray

9. Emission vs. Absorption
Different elements emit different energies of light during relaxation
“Emission Spectra” show what energies of light are emitted during relaxation
The energies absorbed by an element are particular, too
“Absorption Spectra” are a way of representing what energies of light are absorbed by an element

12. Your Job…
Complete the worksheets about kernel structures and the chemistry of light (due tomorrow)
Upcoming Dates:
Thursday QUIZ
Monday TEST