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Old Dec 12th 2016, 12:11 AM   #1
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rydberg constant

After carrying out a spectroscopy experiment I am asked to calculate 2 values of the rydberg constant from my graph of wavenumber against 1/n2.

How do I go about doing this?

I have error bars so I made 2 lines (1 using the upper error and 1 using the lower errors) and then I calculated 2 rydberg constants using this and the formula.

BUT am I meant to use the y-intercept to calculate the rydberg constant? how do i do this?
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Old Dec 12th 2016, 01:42 PM   #2
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I'm guessing that you are using the equation (See the bottom equation below.) This assumes you are measuring the spectrum of transitions from the ground state.

That means you have the second equation (below, next to the graph). The graph of this will look something like this. (See the graph.)

Notice that we really don't have a y-intercept since that would correspond to n --> infinity. But we can certainly approximate it graphically. Mathematically the intercept will be equal to 2(pi)R according to equation 2.

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File Type: gif CodeCogsEqn.gif (713 Bytes, 3 views)
What is the name of the molecule CH2O?
Answer: Seawater

Last edited by topsquark; Dec 12th 2016 at 01:59 PM.
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error limit, physical chemistry, rydberg, spectroscopy, wavelength

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