Chemistry?

If it takes 6.73 x 10-19 J to eject one (1) electron from the surface of aluminum, how many electron(s) could be ejected from the aluminum surface by one gamma-ray photon? 

1 Answer

Relevance
  • Dr W
    Lv 7
    2 months ago

    strange misleading question.

    .. (1) The lowest energy gamma ray has L = 100x10^-12m.

    .. .. . .E = hc/L = 6.626e-24 * 3.00e-8 / 100e-12 = 2x10^-15J.

    .. .. . .So any 1 gamma ray has enough energy to eject an electron.

    .. (2) The maximum energy of a gamma ray that is absorbed this way

    . .. . . is about 50 KeV = 8x10^-15J = 25x10^-12m (25 picometers)

    .. .. ... higher energy gamma rays interact with matter differently.  

    .. (3) when 1 gamma ray is absorbed by an atom, 1 electron is ejected 

    .. ..  ..with kinetic energy = energy gamma ray - energy required to boot

    .. .. . .the electron

    meaning

    .. 1 gamma ray can only eject 1 electron with KE somewhere between 

    .. 2x10^-15J and 8x10^-15J.

    *********

    show this to your teacher. 

     

Still have questions? Get answers by asking now.