The emission spectrum of an unknown element

The energy difference between orbitals decreases as the distance from the nucleus increases. So, an electron transition from orbital 6 to orbital 3 would have a greater energy difference than an electron transition from orbital 6 to orbital 4. This is because the electron in orbital 3 is further from the nucleus than the electron in orbital 4, so it requires more energy to move it.
  • #1
Specter

Homework Statement


The emission spectrum of an unknown element contains two lines - one in the visible portion of the spectrum, and the other, ultraviolet. Based on the following figure and what you have learned about Niels Bohr's model of the atom, account for the difference in energy between the lines.

The diagram given in the question.

PVRW12a2Q1SWYlkESDL9TQ.png


Homework Equations


None

The Attempt at a Solution



The difference in energy between these lines is the result of electrons transitioning from higher orbitals to lower orbitals.The electron transition responsible for ultraviolt light is falling a great distance in the atom creating higer energy and shorter wavelengths.

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I'm not sure if this is correct or not, we didn't really learn much about this in the lesson.
Is there anything I should research to help me better understand the question? Is there anything I should correct in my answer?

Thanks!
 
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  • #2
Specter said:
The electron transition responsible for ultraviolt light is falling a great distance in the atom creating higer energy and shorter wavelengths.
What do you mean by "distance"?
 
  • #3
mfb said:
What do you mean by "distance"?
The electron transition responsible for ultraviolet light jumps to an orbital and the attraction of the nucleus pulls the electron back to a lower energy. The energy that the electron absorbed is emitted, creating short wavelengths and high energy.

Does this make more sense?
 
  • #4
What does the word "distance" mean?
If it refers to anything in space, it is wrong.
Specter said:
and the attraction of the nucleus pulls the electron back to a lower energy.
That doesn't make sense. The electric attraction is what determines the energy of all energy levels. It doesn't "pull things to lower energy levels".
 
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  • #5
mfb said:
What does the word "distance" mean?
If it refers to anything in space, it is wrong.That doesn't make sense. The electric attraction is what determines the energy of all energy levels. It doesn't "pull things to lower energy levels".

What I read in my lesson is this:

"The attraction of the nucleus eventually pulls the electron back to a lower energy level. When it does, the energy that the electron absorbed is emitted. The energy emitted by the atom is the difference in energy between the two energy levels that the electron occupied."

This is about all there is about spectroscopy in this lesson. Everything else is about energy level diagrams and electron configurations.

Is this referring to something different then what the question is asking me to answer? Isn't this saying that the electron jumping to a higher orbital and being pulled back to a lower energy level is what causes the difference in energy?

By distance I mean the electron transitioning from a higher orbital to a lower orbital. An example would be an electron transition from orbital 6 to orbital 2.

I am still confused by this. I have tried finding some info online and I read the lesson multiple times.
 
  • #6
Perhaps part of the problem is the communication here. When we say "higher orbital" and "lower orbital", we don't mean them to be higher and lower as - say - bird and plane. Higher orbital is in general not "more distant" from the nucleus (as opposed to the higher flying plane being more distant from the Earth surface). So the word "distance" in this context can be a bit confusing and is better to be avoided.
 
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  • #7
Borek said:
Perhaps part of the problem is the communication here. When we say "higher orbital" and "lower orbital", we don't mean them to be higher and lower as - say - bird and plane. Higher orbital is in general not "more distant" from the nucleus (as opposed to the higher flying plane being more distant from the Earth surface). So the word "distance" in this context can be a bit confusing and is better to be avoided.

Thanks.

So the difference in energy between the lines is the electron transition from a higher orbital to a lower orbital? For example, if an electron transitions from orbital 6 to orbital 3, would the energy be greater than an electron transition from orbital 6 to orbital 4?
 
  • #8
Specter said:
So the difference in energy between the lines is the electron transition from a higher orbital to a lower orbital? For example, if an electron transitions from orbital 6 to orbital 3, would the energy be greater than an electron transition from orbital 6 to orbital 4?
Right.
 
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