The Rydberg Formula Dr. Lavelle taught us is

This equation gives us the energy of an electron at a particular energy level (

) given that we know the energy level the electron is at (n), the plank constant (h) and the Rydberg constant (R). Thus, the solution of this equation is the energy of one electron only.

From problems in which one electron change energy level, the books gives a formula that helps calculate the change in energy that takes place. This equation is derived from the Rydberg Formula given above. However, Dr. Lavelle does not want his students to have to memorize two equations especially since the first one can be used for problems where an electron changes energy level--although not it one step.

To solve these problems:

1.) Use the formula given above to get the energy of the electron when it's at its final energy level

2.) Use the formula given above to get the energy of the electron when it's at its initial energy level

3.) Do the final energy minus the initial energy to solve for the energy change in the electron