Photon/Electron absorbtion in atoms

[Shameel]

Hi guys,
I have this question I can do the first part but not the second, any help would be appreciated. Thanks in advance! :cool: o:)
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Question 1
A photon with energy of 6.7eV is fired at the mercury, describe what would happen?
Answer
Photon would be absorbed and electron would jump to n=3 (the second excited state) and almost instantaneously electron will return back to the ground state whilst simultaneously emitting a photon (emission spectrum)
Question 2
An electron with 6eV is fired at the mercury, describe what would happen?
Answer
I have no idea, please help!

[Gokul43201]

1. Correct.

2. Let's try and guess something....does the electron just pass right through, or does it collide with something ? If it does, what could this something be ? And if there was a collision, what could happen to the energy of this electron (6eV), after the collision ?

[Shameel]

1. Correct.

2. Let's try and guess something....does the electron just pass right through, or does it collide with something ? If it does, what could this something be ? And if there was a collision, what could happen to the energy of this electron (6eV), after the collision ?
I was thinking that the 6eV electron would impart some of its energy onto the other electron (if it hits it) which would excite the electron to n=2 and the rest of the energy would be the Kinetic energy of the incident electron. I.e. compton scattering?

[Gokul43201]

That's correct. It is a similar process to Compton scattering.