Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: soaring206 on April 24, 2005, 08:22:11 PM
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I'm having a lot of trouble with two of my homework problems tonight. I have been completely through my textbook and all over the internet, but I can't find what I'm looking for anywhere. I have no idea where to even begin on the following two problems, so if someone could just give me a push in the right direction (like an equation or something), I'd greatly appreciate it! :)
1. Calculate the root-mean-square (standard deviation) displacement of the nuclei of 12C16O in the ground state and compare it to the equilibrium bond length of 112.832 pm. (HINT: <x>=0) Use ?=(k?/?2)1/2 and k=1903 kg/s2.
2. Calculate the value of <r> for the n=2, l=1, ml=0 state and the n=2, l=0, ml=0 state of the hydrogen atom.
Any help at all would be appreciated...thank you so much in advance!
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2. Do you know the wavefunction for that state?
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Unfortunately, no...that's all the information given to me in the question.
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Open your book. The wavefunctions are there.
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Oh, right...sorry.
n=2. l=1, ml=0
1/8(2Z3/?a3)1/2(Zr/a)e-Zr/2acos?
n=2, l=0, ml=0
1/8(2Z3/?a3)1/2(2-Zr/a)e-Zr/2a
a=4??0?2/?e2
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Now just take the integral of (phi<r>phi*) and you'll be set.
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Hmm...thanks Mitch. I feel dumb...can't believe I didn't realize that. Lol.
Any ideas on the first one perchance?