Question

The energies, E, for the first few states of an unknown element are given in the table in arbitrary units. 1 п 2 3 4 00 Е -84 -36 -16 -12 0 A gaseous sample of this element is bombarded by photons of various energies in these same units Match each photon to the result of its absorption, or lack thereof, by an n 1 electron. Answer Bank Photon Energy Result nI to n-2 A 84 4 nI to n- 4 B 68 not absorbed C n-1 to n-3 48 electron ejected 63

Answer 1

When photon A is bombarded, the electron gains 84 units of energy

$\Rightarrow$ It's final energy = -84 + 84 = 0

When the electron's energy is 0

$\Rightarrow$ The electron is at infinity. Since the energy of electron at infinity is 0.

$\Rightarrow$ The electron has been ejected.

When photon B is bombarded, the electron gains 68 units of energy.

$\Rightarrow$ It's final energy is -84 + 68 = -16.

This energy corresponds to n=3 state.

At n = 3, the electron's energy is -16

$\Rightarrow$ The electron has gone from n=1 to n=3.

When photon C is bombarded, the electron gains 63 units of energy.

$\Rightarrow$ It's final energy is -84 + 63 = -21

This energy corresponds to no state, thus this energy will not be absorbed by the electron.

When photon D is bombarded, the electron gains 48 units of energy.

$\Rightarrow$ It's final energy is -84 + 48 = -36

This energy corresponds to n=2 state.

At n=2 electron's energy is -36.

$\Rightarrow$ The electron has gone from n=1 to n=2.