When the excited electron in a hydrogen atom falls from to , a photon of blue light is emitted. if an excited electron in falls from , which energy level must it fall to so that a similar blue light (as with hydrogen) is emitted? prove it.

n = 3 for similar blue light

Explanation:

The principle applied here is energy levels and energy changes. There are different energy levels depending on the value of the integer as explained by Max planck - a german physicist in 1900, Max planck claimed that electrons in an atom were presumed to be oscillating with a frequency f, then there enrrgy will be given by the plancks equation ; E =hf, where h is the plancks constant.

In general energy of each level can be written as E =nhf

that's what i got you can count the number of atoms

a is the correct answer