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Atoms – Electron Configuration
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•Molecules:  Multiple atoms sharing/exchanging electrons  (H2O, CH4)
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•Ions:          Single atoms where one or more electrons have escaped  (H+)
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•Binding energy:   Energy needed to let electron escape
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•Permitted “orbits” or energy levels
–By rules of quantum mechanics, only certain “orbits” are allowed
–Ground State:  Atom with electron in lowest energy orbit
–Excited State:  Atom with at least one atom in a higher energy orbit
–Transition:    As electron jumps from one energy level orbit to another,
  atom must release/absorb energy different, usually in form of light.
•Because only certain orbits are allowed, only certain energy jumps are allowed, and atoms can absorb or emit only certain energies (wavelengths) of light.
•In complicated molecules or “solids” many orbits and transitions are allowed
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•Can use energy levels  to “fingerprint” elements and estimate temperatures.
From our text:  Horizons, by Seeds