An electron in a hydrogen atom moves from level 1 to level 4. The electron then drops from level 4 to level 2. Which statement describes the most likely result?

A. The energy absorbed in the first move equals the energy released in the second move.
B. The energy absorbed in the first move is greater than the energy released in the second move.
C. The energy released in the first move equals the energy absorbed in the second move.
D. The energy released in the first move is greater than the energy absorbed in the second move.



Answer :

To understand the problem, we need to evaluate the energy changes as an electron transitions between different energy levels in a hydrogen atom.

First, we evaluate the energy absorbed when the electron moves from level 1 (n=1) to level 4 (n=4). The energy levels of the electron in a hydrogen atom are given by the formula:
[tex]\[ E_n = -\frac{13.6 \text{ eV}}{n^2} \][/tex]

1. Energy at level 1 (n=1):
[tex]\[ E_1 = -\frac{13.6 \text{ eV}}{1^2} = -13.6 \text{ eV} \][/tex]

2. Energy at level 4 (n=4):
[tex]\[ E_4 = -\frac{13.6 \text{ eV}}{4^2} = -\frac{13.6 \text{ eV}}{16} = -0.85 \text{ eV} \][/tex]

Next, we determine the energy absorbed when moving from level 1 to level 4 by finding the energy difference between these two levels:
[tex]\[ \text{Energy absorbed} = E_4 - E_1 = -0.85 \text{ eV} - (-13.6 \text{ eV}) = 12.75 \text{ eV} \][/tex]

The electron then drops from level 4 to level 2. We need to calculate the energy at level 2 (n=2):
[tex]\[ E_2 = -\frac{13.6 \text{ eV}}{2^2} = -\frac{13.6 \text{ eV}}{4} = -3.4 \text{ eV} \][/tex]

We then determine the energy released when the electron moves from level 4 to level 2:
[tex]\[ \text{Energy released} = E_2 - E_4 = -3.4 \text{ eV} - (-0.85 \text{ eV}) = -3.4 \text{ eV} + 0.85 \text{ eV} = -2.55 \text{ eV} \][/tex]

By comparing the magnitudes of the absorbed and released energies, we find:
- Energy absorbed when moving from level 1 to level 4 is [tex]\( 12.75 \text{ eV} \)[/tex]
- Energy released when moving from level 4 to level 2 is [tex]\( -2.55 \text{ eV} \)[/tex] (the negative sign indicates a release of energy)

Thus, the energy absorbed in the first move is greater than the energy released in the second move.

Therefore, the correct statement is:
The energy absorbed in the first move is greater than the energy released in the second move.