Chemistry Question Rydberg Constant in kj/mol

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RIPP_n_WIPE
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Chemistry Question Rydberg Constant in kj/mol

Post by RIPP_n_WIPE »

Hey I'm doing a lab on Hydrogen emission spectra (obviously) and the lab book in question (Chemistry in the Laboratory Sixth Edition; Postma, Roberts, Hollenberg) says

"Using a form of the Rydberg Equation

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Change in E = hv = hc/wavelength =Rydberg contant((1/final state^2)-(1/initial state^2))

calculate for each of the three lines you measured a value for the Rydberg constant, in units of kj/mol of photons. The constant relates the energy change (kj/mol) of a given transition to the principle quantum numbers for the transition"

K my problem is that the Rydberg constant is 1.0974x10^7 m^-1 and I'm getting my answer as 1.0815x10^7 kj/mol. Now am I right and just not seeing it or do I somehow have to convert Rydberg constant as it stands from m^-1 to kj/mol.
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Eris
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Post by Eris »

The Rydberg constant allows the equation to spit out a value for the wavelength of the photons emitted. The wavelength of the photons is directly proportional to their energy, in accordance with the Planck relationship. Then you know the joules per photon, and you simply have to multiply by Avogadro's number and you get energy per mole of photons.
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