Download Chemistry 112

Models of the Atom
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A shortcoming of the discovery of the nucleus
and advancements in an atomic model was
that it failed to explain chemical behavior
A model that focused on the electron was
needed
Bohr built on Rutherford’s model to include
the energy within an atom
◦ He suggested that electrons existed within circular
paths, called orbitals, outside the nucleus
◦ Every electron within an orbital possesses a certain
amount of energy
 They were then called energy levels
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The e- with the lowest energy are found in
the first energy level
e- can move from one orbital to another but
only if it gains or loses energy
The further an e- is away from the nucleus,
the more energy it possesses
The amount of energy an e- must
absorb/release to move from one orbital to
another is called a quantum
◦ The amount of energy to move from one orbital to
the next is not always the same
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The model of the atom was better understood
but still failed to explain all the properties of
atoms with atomic numbers greater than
hydrogen
Information was being gathered by other
scientists on waves and energy that did not
correspond with Bohr’s model
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Schrodinger used information about electron
motion to devise and solve a mathematical
equation that described the behavior of the
electron
The amount of energy an e- possesses is still
considered fixed but the pathway is not
QMM takes into consideration the amount of
energy an e- has and how likely it is to be
found in a certain location (probability)
e- are most likely to be found close to the
nucleus