Which of the transitions in the hydrogen atom energy-level is the longest wavelength photon?
1 Answer
I'm not entirely sure that I understand your question, but the longest wavelength would belong to the red colored light.
When an electron drops from energy level 3 to energy level 2, red light is emitted. The red light has the longest wavelength, lowest energy, and lowest frequency.
The shorter the drop from one energy level to another, the less energy, in the form of light/photons is emitted. I hope this helps.
