Niels Bohr proposed a model for the hydrogen atom that explained the spectrum of the hydrogen atom. The Bohr model was based on the following assumptions.
Here is a good site for a more detailed development of the Bohr theory of the atom. This site also has two problems for you to practice.
Using the above assumptions, the energy of a hydrogen atom in level n was found to be
E = -RH/n2 where RH = 2.179 x 10-18
We can then calculate the change in energy when an electron changes from n=3 to n=2
E = E3 - E2 = (--RH/32) - (--RH/22) or
E = -RH(1/22 - 1/32) which also must be equal to h*.
Solving for gives
= E/h = RH/h * (1/22 - 1/32) which gives
RH/h = 2.179 c 10-18J/6.626 x 10-34Js or
RH/h = 3.289 x 1015s-1
This is within experimental error of the constant in the Balmer equation for a hydrogen transition series (3.2881 x 1015s-1) which really made everyone take notice.
Go here to obtain further insight into the Bohr model of the atom. Be sure to click on "Next" at the bottom of this site to continue with the explanations.
However, the Bohr model
People tried modifying the theory by allowing the electrons to have elliptical orbits and other changes, but when you have a bad model you need to start over and that is what we will do next.
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