Question

What hydrogen atom transitions represent emission of the longest wavelength photon?

Answer 1

Wavelength has inverse relationship with its energy. The shorter the wavelength, the higher the energy.

Complete question was:
Which of the following transitions (in a hydrogen atom) represent emission of the longest wavelength photon?n = 1 to n = 2 n = 3 to n = 1 
n = 3 to n = 4 
n = 4 to n = 2 
n = 5 to n = 4

The longest wavelength photon is n = 5 to n = 4. As I stated above,the wavelength and energy has inverse relationship. The longest wavelength has the lowest energy.

Answer 2

The correct answer is:

The longest wavelength photon is n = 5 to n = 4.

The explanation:

According to he relation between the wavelength and energy, there have inverse relationship. The longest wavelength has the lowest energy.

and when:

-Transitions to n=1 are in the UV part of the spectrum and have the shortest wavelengths.

-and Transitions to n=2 are in the visible part of the spectrum and have wavelengths between 700nm and around 400 nm

-and Transitions to n=3 or greater are in the infra-red part of the spectrum and have the longest wavelengths.

- So the longest wavelength would correspond to the lowest energy and that would correspond to the difference in energy between n=5 and n=4