asas t PowerPoint

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Science, Technology and Environment
Laboratory, Pedagogical Department
P.E., University of Athens, Greece
Hands-on spectrum lines Introducing microscopic
quantum explanations of the emitted photons to
non-physics majors students
Vassilis Dimopoulos, George Kalkanis
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The Contents
duality of light/electron
mechanic waves
spectrum
early models of atom
quantum model for the atom of hydrogen
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A spectroscope is used in order to observe the
continuous and linear spectra of various lights.
Continuous spectrum
Emission line spectrum
The line spectra serves as a key to the structure
of the atom, since any atomic theory must be able
to explain why atoms emit light of discrete
wavelengths and should be able to predict what
these wavelengths are.
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?(r, ?, f) R(r) T(?) F(f)
Some of the wave functions for the atom of
Hydrogen
Back
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The wavefunction cannot been pictured
The ?2 is a real number and gives the probability
per unit volume that the particle will be found
at any given point. The ?2 is called the
probability density (Serway, 1986)
In a dots representation the value of ?2 is
higher when the density of the dots is high
The probability density is also called
electronic density or electronic cloud
Back
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We can use the radial probability distribution in
order to calculate the probability of finding the
electron within the area x lt r lt y (Serway,
1986).
Having calculated the probability we converse
this number to the frequency of finding the
electron in different areas for each state.
Back
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The probability of finding a sphere / unit of
surface increases
If we move on a circle the higher probability of
finding a sphere is on a circle of a specific
radius
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The representation of ?2 is different to the
representation of P(r)
Back
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The representation of ?2 is different to the
representation of P(r)
Back
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The representation of ?2 is different to the
representation of P(r)
Back
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Emphasis is on the microscopic explanation of the
spectrum of hydrogen
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An energy diagram is used in order to confront
that a spectral line can be created only by
transitions between two discrete energy levels