MCQ
Which electron level would allow the hydrogen atom to absorb a photon but not emit a photon
- A$3s$
- B$2p$
- C$2s$
- ✓$1s$
✓
Answer
Correct option: D.
$1s$
d
$1s$ electronic level would allow the hydrogen atom to absorb a photon but not to emit it. On absorption of radiation, electron will be transferred from is level to higher level such as $2 s$ or $3 s$. But to emit a photon, the electron should go to the lower energy level from higher energy level. Since is is the lowest energy level, the electron cannot go to a lower level. Hence, emission is not possible.
$1s$ electronic level would allow the hydrogen atom to absorb a photon but not to emit it. On absorption of radiation, electron will be transferred from is level to higher level such as $2 s$ or $3 s$. But to emit a photon, the electron should go to the lower energy level from higher energy level. Since is is the lowest energy level, the electron cannot go to a lower level. Hence, emission is not possible.
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