H-Atom ($E_{n}=-\frac{hR}{n^{2}}$)

304922790
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Joined: Fri Sep 29, 2017 7:04 am

During the lecture, Lavelle showed us (En=-hR/(n^2), the other form of the Rydberg equation. Can I use this equation instead of the Z-indpendent Rydberg equation to solve this problem?

The problem is:
The energy levels of hydrogenlike one-electron ions of atomic number Z differ from those of hydrogen by a factor of Z^2. Predict the wavelength of the transition from n=2 to n=1 in He+ .

Chem_Mod
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### Re: Question about 1.17  [ENDORSED]

Yes, you can. In this case, since it’s helium we’re looking at, we have to take into account Z=2. The equation is En = -(Z2)(h*R/n2). You can then find the change in energy by subtracting Efinal and Einitial to get the energy of the light. From there, use the E = (h*c)/lambda equation to find lambda.

veneziaramirez 3I
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Even though it is He^+ we would still make Z 2? So if it is a one-electron ion, we would use how many the element originally has?

Chem_Mod
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Z by definition is atomic number. Since atomic number determines the element, we would still use Z=2, even though it lost an electron.

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