## Sig Figs when using E=-hR/n^2?

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

sofiakavanaugh
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### Sig Figs when using E=-hR/n^2?

Hi,

I was going through homework problems and I was a little confused when it comes to sig figs when you use the equation E=-hR/n^2, because there doesn't seem to be much to go off of. For example, 1.13 asks for the wavelength of radiation generated from the n=4 to n=2 transition. I understand how to do the problem, but how many sig figs would your final answer be and why? I noticed the textbook used 3, but that seems somewhat random; would it be the number of sig figs that the R constant has?

Thanks,
Sofia Kavanaugh

Chem_Mod
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### Re: Sig Figs when using E=-hR/n^2?

Correct, the sig figs, in this case, are determined by the sig fig in the given values for h and R. I mentioned this in class when I did the example calculation.