## Spectral Lines

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

Simon Dionson 4I
Posts: 107
Joined: Sat Sep 14, 2019 12:17 am

### Spectral Lines

1A.11 - This question is asking me about classifying lines to a series (i.e. Balmer or Lyman). Is there a significance of the lines appearing towards certain regions of the light spectrum?

Justin Vayakone 1C
Posts: 110
Joined: Sat Sep 07, 2019 12:19 am

### Re: Spectral Lines

Location on the electromagnetic spectrum doesn't exactly determine which series a line belongs to. Each line represents energy released by the movement of a hydrogen electron from one energy level to a lower energy level. Each energy level is represented by what's called the principal quantum number (n). What's common among each series is that their lines all involve the electron being in the same final energy level. For example, each line in the Balmer series has the electron's final location at the lower energy level n=2, but every line has the electron beginning in a different energy level above n=2. One line could be an electron moving from n=3 to n=2 while another line could be from n=4 to n=2. As long as the final energy level is the same, the lines are in the same series.

Astrid Lunde 1I
Posts: 103
Joined: Sat Sep 07, 2019 12:16 am

### Re: Spectral Lines

Justin Vayakone 4H wrote:Location on the electromagnetic spectrum doesn't exactly determine which series a line belongs to. Each line represents energy released by the movement of a hydrogen electron from one energy level to a lower energy level. Each energy level is represented by what's called the principal quantum number (n). What's common among each series is that their lines all involve the electron being in the same final energy level. For example, each line in the Balmer series has the electron's final location at the lower energy level n=2, but every line has the electron beginning in a different energy level above n=2. One line could be an electron moving from n=3 to n=2 while another line could be from n=4 to n=2. As long as the final energy level is the same, the lines are in the same series.

So for the Balmer series it doesn't matter were the electron begins, but as long as it ends at n=2, which is the visible light.

Posts: 51
Joined: Sat Aug 24, 2019 12:16 am

### Re: Spectral Lines

In the Balmer series, electrons end at n=2. Because the drop from higher energy levels to n=2 is not as large as the drop to n=1, comparatively less energy is emitted. This is why the emitted light is in the visible spectrum.

In the Lyman series, electrons end at n=1. The drop to n=1 from n=2 (or n>2) is quite large, so more energy is emitted. Thus, the light emitted from this drop is in the UV spectrum.