Nature of Light

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C.A. Coulson
Linus Pauling
(1910 1974)
(1901 1994)
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Edward Frankland (1825 1899)
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Group 5A Elements
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When the formulae of inorganic chemical compounds
are considered, even a superficial observer is
impressed with the general symmetry of their
construction. The compounds of nitrogen,
phosphorus, antimony, and arsenic, especially,
exhibit the tendency of these elements to form
compounds containing 3 or 5 atoms of other
elements and it is in these proportions that
their affinities are best satisfied thus in the
ternal group we have NO3, NH3, NI3, NS3, PO3,
PH3, PCl3, SbO3, SbH3, SbCl3, AsO3, AsH3, AsCl3,
etc. and in the five-atom group, NO5, NH4O,
NH4I, PO5, PH4I, etc. Without offering any
hypothesis regarding the cause of this
symmetrical grouping of atoms, it is sufficiently
evident from the examples just given, that such a
tendency or law prevails, and that, no matter
what the character of the uniting atoms may be,
the combining power of the attracting element, if
I may be allowed the term, is always satisfied by
the same number of these atoms.
Phil. Trans. Royal Soc. 1852
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Richard Abegg (1869 -1910)
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Abeggs Rule
The difference between the maximum positive and
negative valence of an element is frequently
eight.
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Nature of Light
Christiaan Huygens (1629 1695)
Isaac Newton (1643- 1727)
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Properties of Waves
Reflection
Refraction
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Diffraction
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Interference
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Properties of Light
Refraction
Reflection
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Reflection of Light Corpuscles
Refraction of Light Corpuscles
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Huygens Construction
Huygen Construction for Reflection
Huygen Construction for Refraction
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Youngs Double Slit Experiment
Thomas Young (1773 1829)
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Laser Source for Double Slit Experiment
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Interpretation of the Double Slit Results
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Fresnels Dot
Augustin Jean Fresnel (1788 1827)
Simeon Poisson (1781 1840)
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Maxwells Equations
James Clerk Maxwell (1831 1879)
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Electromagnetic Radiation
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Heinrich Hertz (1857 1894)
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Light is a Wave
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Blackbody Radiation
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Cavities as Blackbodies
http//mediaserve.nmt.edu/portal/app/EODILecturePo
rtal.html
http//breeze.nmt.edu/st589dchemnatblackbody/
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The Ultraviolet Catastrophe
Lord Rayleigh
James Jeans
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Max Planck (1858 1947)
After a few weeks of the most strenuous labor of
my life, the darkness lifted and a new,
unimagined prospect began to dawn.
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Photoelectric Effect
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Albert Einstein (1879 1955)
Robert Millikan (1868 - 1953)
Einsteins equation was a bold prediction, for at
that time there was no evidence that Plancks
constant had any applicability outside of
blackbody radiation and there were no
experimental data on the kinetic energy as a
function of frequency.
Physics by Paul A. Tipler
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Millikans Photoelectric Data
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The Double Slit Experiment Revisited
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Light is a Particle