now, emission spectra is a series of lines form when the mid light is focused by his splint and passes through a prison. So remember we have our atom here and here. We have our first shell. And theoretically there's an infinite number of shells within a given out. We haven't found all the elements in the universe. So there are elements out there that we still don't know about. So the number of shells is infinite. And we're going to say here, we have an electron that's at a higher energy state and higher energy level. And what's going to happen is eventually it starts to come back down to its ground state. So it's dropping back down to the first shell. Remember as an electron drops back down from a higher shell to lower shell, it emits energy. This energy is emitted as light. What happens here is a slip will focus this energy, and what happens there is it passes through a prison. This prism allows us to split that energy into its various wavelengths and create this emission spectrum. So remember, a slit is just a narrow, long, narrow cut youth to spread closely packed wavelengths, which can later be measured. So we can examine this electron emission spectrum and we can measure the wavelength of each one of these colored blinds. Just realize you that the prism itself, it helps to transform these wavelengths into discrete lines on the emission spectrum. So all that's really going on here is we're focusing the emitted energy as an electron drops from a higher shell number down to a lower shell number and imposing them on emission spectrum. From there, we can calculate their wavelengths and in that way also calculate the energy and or frequency of these different wavelengths of light.