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Quantum Atom. Problem. Bohr model of the atom only successfully predicted the behavior of hydrogen Good start, but needed refinement. Heisenberg Uncertainty Principle. It is not possible to know both the position and momentum ( mv ) of an electron
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Problem • Bohr model of the atom only successfully predicted the behavior of hydrogen • Good start, but needed refinement
Heisenberg Uncertainty Principle • It is not possible to know both the position and momentum (mv) of an electron • Cannot assume that the electron is moving around the nucleus in a well-defined orbit as in the Bohr model
Louis de Broglie • Suggested matter that is assumed to be of a particle nature, does have wavelike properties • Developed an equation for actually calculating this wavelength of matter • For very small particles, wavelength is significant
Wave Function • Erwin Schrodinger developed a series of equations that describe the areas of probability of finding an electron • There are different values of these wave functions that occur at different energy levels • Wave function are called Orbitals
Quantum Mechanics • Describes mathematically the properties of an electron • Shows regions of probability of finding an electron
Quantum Numbers • Principal Quantum Number (n) – same as the Bohr energy level • Also called shells • Range from n=1 to n=7
Subshell or Sublevel • Angular Momentum Number • Come in four types • s subshell (spherical) • p subshell (dumbbell) • d subshell (four lobes) • f subshell
Orbital • Magnetic Quantum Number • These are the orbitals (hold 2 e- each) • Each sublevel may have more that one orbital with a different orientation in space • s ( 1 orbital) • p ( 3 orbitals) • d (5 orbitals) • f (7 orbitals)
Degenerate Orbitals • Orbitals that have the same energies
Electron Spin Number • Electron behaves as if it is spinning on its axis • Fourth Quantum number is the spin number
Pauli Exclusion Principle • No two electrons can have the same set of four quantum numbers • If an orbital has two electrons in it, they must have different spins • Electrons in the same orbital with different spins are called paired electrons