When an electron in H changes its spin from the same to the opposite direction as the proton,it:

Question

Quizplus · Accepted Answer

When an electron in hydrogen changes its spin direction from the same to the opposite direction as the proton, it undergoes a spin-flip transition. This results in the emission of a radio wave photon. Therefore, choice C is the correct answer. Neither X-ray nor visible light photons are involved in this process, making choices A and D incorrect. Also, there is no absorption of any kind of photon during this transition, making choice B incorrect as well. When an electron in H changes its spin from the same to the opposite direction as the proton, it emits a radio wave photon. This is known as the 21 cm line, and it is commonly used in radio astronomy to study the distribution of hydrogen in the universe.

When an Electron in H Changes Its Spin from the Same