Hydrogen Spectrum: Lyman, Balmer, Paschen & Pfund Series

[Amith2006]

# A continuous band of radiation having all wavelengths from about 1000 Angstrom to 10000 Angstrom is passed through a gas of monoatomic hydrogen. In the emission spectrum one can observe the entire:
a)Lyman series
b)Balmer series
c)Paschen series
d)Pfund series
I just don't have any idea about it. Please help!

 

[dmoravec]

When passing the continuous band of radiation through the monoatomic hydrogen many of the particles became exited. That is, the electron associated with that molecule went to a higher energy level orbital. The energy level can be assigned a principle quantum number (n=1,2, etc) in which the higher the number the further away from the nucleous the orbital lies and the higher the energy it has.

The series you are talking about (Lyman, Balmer, etc) are just names assigned to the sets of wavelengths that are released by the hydrogen atom as the electron goes back to a lower energy level. By conservation of energy, when the electron goes to a lower energy orbital the energy must be conserved, so it let's off electromagnetic radiation. For example, the Lyman Series consists of all of the wavelengths in which the electron is going all the way back to the first energy level (n=1). This electron could come from the second (n=2), third (n=3), or whatever energy level it was in. Likewise, the Balmer series is the series where the electron is going from a higher energy level down to the second energy level (n=2).

The two most common being the Lyman and Balmer exist in the Ultraviolet spectrum and visable spectrum respectivly.

A little more can be read about here:
http://hyperphysics.phy-astr.gsu.edu/hbase/hyde.html

Hope that helps!