07+Atomic+Structure+and+Periodicity - AP Chemistry ATOMIC STRUCTURE ELECTROMAGNETIC RADIATION James Maxwell developed an elegant mathematical theory in

07+Atomic+Structure+and+Periodicity - AP Chemistry ATOMIC...

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AP* Chemistry ATOMIC STRUCTURE *AP is a registered trademark of the College Board, which was not involved in the production of, and does not endorse, this product. © 2008 by René McCormick. All rights reserved. ELECTROMAGNETIC RADIATION James Maxwell developed an elegant mathematical theory in 1864 to describe all forms of radiation in terms of oscillating or wave-like electric and magnetic fields in space. electromagnetic radiation —UV, visible light, IR, microwaves, television and radio signals, and X-rays wavelength ( λ ) —(lambda) length between 2 successive crests. frequency ( υ ) —(nu in chemistry; f in physics—either is OK), number of cycles per second that pass a certain point in space (Hz-cycles per second) amplitude —maximum height of a wave as measured from the axis of propagation nodes —points of zero amplitude (equilibrium position); always occur at λ /2 for sinusoidal waves velocity —speed of the wave velocity = λ υ “c”—the speed of light; 2.99792458 [just call it 3] × 10 8 m/s; ALL EM RADIATION TRAVELS AT THIS SPEED! I call it easy, you’ll call it a trick! If “light” is involved, it travels at 3 × 10 8 m/s Notice that λ and υ are inversely proportional. When one is large, the other is small. axis of propagation
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