Posts Tagged ‘James Chadwick’

Quantum Leap: Chemistry

Friday, May 14th, 2010

Guest author, Thomas Kennedy, features a twice-monthly series, Quantum Leap, wherein he guides readers through the fascinating world of quantum mechanics. This is issue 013.
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*This issue is continued from Issue 012, “Uncertainty

Note: Just as no map can equal a territory, no concept of an atom can possibly equal its nature.   These models of the atom simply served as a way of thinking about them, albeit they contained limitations, as all models do.

http://www.nobeliefs.com/images/atoms18.gif

Although the mathematical concept of the atom got better, the visual concept of the atom got worse.  Regardless, even simplistic visual models can still prove useful.  Chemists usually describe the atom as a simple solar system model similar to Bohr’s model, but without the different orbit shapes.  The important emphasis for chemistry medium attempts to show the groupings of electrons in orbital shells.  (The example above shows the first eleven elements.)

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Quantum Leap: Charge!

Saturday, March 20th, 2010

Guest author, Thomas Kennedy, features a twice-monthly series, Quantum Leap, wherein he guides readers through the fascinating world of quantum mechanics. This is issue 010.
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In 1896, Henri Becquerel inadvertently discovered radioactivity.  “Investigating the work of Wilhelm Conrad Röntgen, Becquerel wrapped a fluorescent substance, potassium uranyl sulfate, in photographic plates and black material in preparation for an experiment requiring bright sunlight.  However, prior to actually performing the experiment, Becquerel found that the photographic plates were already exposed, showing the image of the substance.  This discovery led Becquerel to investigate the spontaneous emission of nuclear radiation.”*

“Becquerel gave up further investigation of this finding but the research was pressed on by Marie and Pierre  Curie, with Marie initially deciding to further the work regarding the “mysterious uranium rays.” (more…)