## Rydberg formula

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

Guzman_1J
Posts: 72
Joined: Wed Sep 18, 2019 12:16 am

### Rydberg formula

Which is the Rydbger formula? In the texbook it shows it as 1/wavelength=Rh((1/n1^2)-(1/n2^2) but while solving a problem in discussion that asked for it, a student used En=hR/n^2 but I did not see that formula in the texbook for part 1A. I have missed lecture in one of the past weeks so I might have missed this information.

Brian Tangsombatvisit 1C
Posts: 119
Joined: Sat Aug 17, 2019 12:15 am

### Re: Rydberg formula

The En=hR/n^2 formula represents the energy an electron has when it is in the nth shell. The Rydberg equation, 1/wavelength=Rh((1/n1^2)-(1/n2^2), is derived from the change in energy formula, which is final energy - initial energy, meaning that it is delta E = Ef=hR/n^2 - Ei=hR/n^2. To get the Rydberg equation from this formula, they just divided all the terms by h, planck''s constant. I wouldn't try to memorize the Rydberg equation. Instead, I would memorize the formula for the energy of an electron, En=hR/n^2, because it makes more sense to me conceptually.

Ananta3G
Posts: 62
Joined: Wed Sep 18, 2019 12:19 am

### Re: Rydberg formula

If I am understanding the topic/your question correctly, the equation, En=hR/n^2, is the equation used to find the energy emitted by an H atom when an electron makes a transition from one quantum level to another. The equation does use the Rydberg Constant: 3.29 x 10^15 Hz. The equation in the textbook just seems to be another form of that equation where the initial and final n are already inputted to represent "E final - E initial" to mean the energy released and the formula for frequency is already inputted too. Hope this explanation helps!