Quantized Energy and Light 11/13/13

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

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

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

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

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

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

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

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