Mercury Energy Levels

[danielf]

I came across the question in a TSFX paper I don't really understand:

An energy level diagram is shown with Ground (0eV), 1st excited level (4.9eV), 2nd (6.7eV), 3rd (8.8eV), and Ionisation Level (10.4eV)

The question is:
The mercury vapour is bombarded with 10.2eV electrons. What possible energies could the emerging electrons have (one or more answers)?

A: 0.4eV
B:1.4eV
C: 3.5eV
D: 5.3eV
E: 10.2eV
F: All of the above

The answer given is F (all of the above). I originally thought that the answer was none of these because no electrons are given sufficient energy to be freed. Even if it was a misprint and they meant emerging photons how did they get 10.2eV?

Please help???

[cara.mel]

Electron hits the bunch of mercury, some energy is given to the mercury stuff to move its electrons to a higher energy level, the original electron passing through has now got less energy

It can emerge with:
10.2eV if it doesn't hit anything
5.3 if it causes something to move from ground state -> 1st excited level
etc
0.4eV comes about if your electron with 5.3eV left makes another atoms electron go from ground -> 1st, thats the other tricky one.


Note: it is photons where the energy of them must match the difference in energy levels for anything to happen. I know this explanation is insufficient (how can it be exactly a difference in energy level, how can you get exact quantities, wouldn't there need to be a bit of leeway for it to work). I cannot answer this yet

[danielf]

No that makes perfect sense - The 0.4eV seems a tad tricky for a VCE paper tho