## Q. 1.57

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

Linda Arroyo 3J
Posts: 15
Joined: Fri Apr 06, 2018 11:01 am

### Q. 1.57

Q. Lines in the Balmer series of the hydrogen spectrum are observed at 656.3, 486.1, 434.0, and 410.2 nm. What is the wavelength of the next line in the series?
I;m having difficulty with this problem, I understand what the next n would be, it would be 7. But with knowing that what would I do next? do I use the v=R(1/N^2i-1/N^2f) or En=-hR/n^2? are they the same and which one should I use ?

Andrea- 3J
Posts: 56
Joined: Tue Nov 14, 2017 3:00 am

### Re: Q. 1.57

You find the change in energy using :
ΔE= Ef-Ei=-(hR/n^2f)-(-hR/n^2i)

To find the wavelength you use:
λ=E/⋎ and E=h⋎

Melody Zhang 3L
Posts: 35
Joined: Fri Sep 28, 2018 12:21 am

### Re: Q. 1.57

The two are essentially the same but I think we need to use En=-hR/n^2 for the class.