Chapter 11: Introduction to Modern Atomic Theory

Bohr's model of the hydrogen atom failed to predict the emission spectrum of helium, so a new model had to develop which could do a better job. Bohr's model was good for hydrogen, it just did not work for any other element.

In the new model some features of the Bohr model could not be abandoned: quantized energy levels for example. It was this idea that explained the discrete lines in the emission spectrum for any element.

When other scientist's studied the problem new experiments revealed that electrons exhibited wave behavior. This was very strang. Electrons acting like waves!

When scientist thought of the electron as a wave. Thinking about the electron as a wave meant the behavior of the electron was totally different.

Scientist's found that it was not possible to know exactly what the energy and the position of the electron. This introduces the concept of the probability of finding the electron. We can not know exactly the location or how the electron moves.

So the electron occupies a three dimension region of space...an orbital.

So we only know the electron is likely to be found in a particular region of space.

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