Quantum mechanics - CHEM10004 help

[ChickenCh0wM1en]

Hi guys, seeing that QM is just retarded I wanted to make a threead.

Ill get it started off.

Would anyone have any idea how to do these qns?

[lzxnl]

5.3
Well...ionisation energy I'm fairly sure refers to the energy required to strip a single atom of an electron, i.e. gaseous sodium not solid sodium, but oh well.
Threshold frequency = frequency of light to just excite an electron
So multiply by Planck's constant and you'll have your answer. 18.2 eV apparently which seems a bit large o.O

5.4
206 kJ for a mole of electrons => for a single electron, energy required = 206000J/(6.02*10^23)=3.422*10^-19 J
Light of wavelength 254 nm has energy hc/254nm = 7.826*10^-19 J
So take the difference; KE max = 4.40*10^-19 J

5.5
Radiation with a wavelength of 1nm has a momentum of h/1nm = 6.626*10^-25 Ns
Which is the largest amount of momentum the radiation could give to the electron.