## Rydberg Constant

Anthony_3C
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### Rydberg Constant

In the Equation that Schrodinger found: $En = -\frac{hR}{n^2}$, the Rydberg constant according to the text book is 3.29 X 10^15 Hz. However, in the hint section for a question on Sapling, it says R = 10 973 731.6 $m^{-1}$. Which one should I use??

George Cazares 1E
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### Re: Rydberg Constant

I believe 3.28984x10^15 Hz is more commonly used in this course, and Lavelle has 3.28984x10^15 Hz as the value of the Rydberg constant on the constants and equations sheet. But, I'm not sure if R = 10 973 731.6 m-1 could be used as well to solve the question on Sapling.

Leyna Tran 2D
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### Re: Rydberg Constant

I also think that we use 3.29 X 10^15 Hz for the rydberg constant.

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### Re: Rydberg Constant

These constants are technically the same, they are just in different units. The 3.29 x 10^15 is in Hz. This would be used if you're using frequency in the problem. The other constant is in meters, and it would be used when using wavelength in the problem. Hope this helps!

Will Skinner
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### Re: Rydberg Constant

Both are correct, but that equation takes R in Hz.

Mahika More 1H
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### Re: Rydberg Constant

Since they are in different units, you can just check your units to see which one to use. Most commonly the value in Hz is used.

Jasraj Parmar 3H
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### Re: Rydberg Constant

I think you use 3.29 x 10^ 15 as the Rydberg Constant for Hz.

Chem_Mod
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### Re: Rydberg Constant

Either can be used, just make sure your other values when using the equation have units that will match/cancel out!

Alex Benson
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### Re: Rydberg Constant

Both of these can be used it is just a matter of making sure that the units all cancel out!

LuveiaPangilinan 2C
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### Re: Rydberg Constant

Both are the same it's just that the other value, R is used in Hz. Hope that helps!

Isabelle Hales 3L
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### Re: Rydberg Constant

Hi! I had a question related to the Rydberg constant. I kept seeing "Rydberg constant for hydrogen" when I was looking up the value of the constant. Does the constant change depending on which element is involved?

John_Tran_1L
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### Re: Rydberg Constant

In one of Lavelle's recent lectures, I recall him using the number 3.29 X 10^15 Hz as the constant.

Andre Fabian 1G
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### Re: Rydberg Constant

Both are correct, but you would use either depending on the context. A good way to check which one to use is to make sure that the units cancel out in whichever equation you're using, or that you don't have any units leftover that wouldn't apply to the answer.

Hope this helps!
Andre

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Joined: Wed Sep 30, 2020 9:54 pm

### Re: Rydberg Constant

Isabelle Hales 3L wrote:Hi! I had a question related to the Rydberg constant. I kept seeing "Rydberg constant for hydrogen" when I was looking up the value of the constant. Does the constant change depending on which element is involved?

I just searched a little about it, and I found that while there are different symbols for the Rydberg constant for hydrogen and the Rydberg constant for heavy atoms, the constant number never changes. I hope this helps!