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Electron Configurations Schrodingers Quantum Model Principal
Energy Levels - A region around the nucleus of an atom where the
electron is likely to be moving.The principal energy levels (n) are
assigned values in order of increasing energy The average distance
of the electron from the nucleus increases with increasing energy
levels. (1 is closest to nucleus.)There are 7 energy levels = 7
periods.
Energy SublevelsEnergy sublevels can be thought of as a section
of seats in a theater. The rows that are higher up and farther from
the stage contain more seats, just as energy levels that are
farther from the nucleus contain more sublevels. The number of
energy sublevels is the same as the number of principal energy
levels. 7Sublevels are labeled __s___ , ___p__ , __d___ , and
__f___according to the shapes of the atoms orbitals
Atomic Orbitals Atomic orbitals represent the electron
probability clouds of an atoms electrons.Each orbital may contain
at most ____2____ electrons.All s orbitals are sphericalAll p
orbitals are dumbbell-shaped4 out 5 d orbitals are flower-shaped
and one has a unique shape7 f orbitals have different and very
complex shapes
Shortcuts Noble Gas Notation method used to represent electron
configurations of noble gases using bracketed symbols.Practice: Use
shortcut method to write e-configurations for Ar and P.
Ar: [Ne] 3s2 3p6 or [Ar]P: [Ne] 3s2 3p3
Ground State vs. Excited StateGround State The most stable,
lower energy arrangement of the electrons in an atom. (The
electrons are in the correct order of orbitals.)Excited State When
atom gains energy the electrons jump into higher energy
level.Identify the following atoms and describe their state.
(Ground or
Excited)1s22s22p63s23p64s13d104p31s22s22p63s23p64s23d104p51s22s22p63s23p64s23d104p65s24d8
Electron Configuration How to show the arrangement of electrons
Aufbau Principle Electrons enter orbitals of lower energy first.
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f,
6d, 7p
Pauli Exclusion Principle No more than __2______ electrons can
occupy the same orbital AND they must spin in opposite direction
(Opposite spins help hold e- in an orbital by creating magnetic
attraction.)
Hunds Rule Orbitals of equal energy must EACH have _1____
electron with the same ____spin______ before any orbital is
occupied by a 2nd electron.
Energy Level Increase
In your book.Copy table 5-2 on p. 134Copy Figure 5-17 on p.
135
