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Question regarding the d Orbitals

  1. Apr 17, 2005 #1
    hey everyone! good morning!

    can anyone please clarify this statement for me?

    True of False (correct statement if false)

    There are five d orbitals at both the fourth and sixth principal energy levels.

    i said it was false because there's only one d orbital per principal energy level. now i know that that is completely wrong (what i said was wrong) but i guess i'm just having a hard time understanding what the principal energy levels are and what that mean...that statement was actually true, but can anyone help me understand why its true? :smile:

    thanks alot!!
  2. jcsd
  3. Apr 17, 2005 #2
    I believe that there are five orbitals in any d shell, but I think this may be a problem of vocabulary. If orbital means the item that holds two electrons, then yes there are 5 of them.

    At the 4th and 6th principle energy levels:

    [tex] 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 [/tex]

    The fourth principle energy level has a coefficient of 4 in the above electron configuration. You can write it out to the 6th level but I'm not sure how it goes after that. as you can see the d shell on the fourth energy level has 5 orbitals, since it holds 10 electrons.
  4. Apr 17, 2005 #3


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    In spectroscopic notation "d" stands for [itex] l=2 [/itex] to which 5 possible values for [itex] m_{l} [/itex] correspond.Therefore,it doesn't matter what the value of [itex] n\geq3 [/tex] is.

  5. Apr 17, 2005 #4
    Good call dex. Quantum numbers never lie.
  6. Apr 17, 2005 #5

    Thank you for the help but i appologize because i'm a little slow...i still don't get it. :confused: so the 4th principle energy level is the [tex]4s^2[/tex]? That one? but i only see two, because of the superscript 2, unless i'm missing something here...how does the d shell hold five? please help me! :cry:

    thanks to both of you btw!
  7. Apr 17, 2005 #6


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    What is principle energy level?Never heard of this notion.Care to explain?

  8. Apr 17, 2005 #7
    Each principle energy level has different types of orbitals (except for the first, of course). The fourth energy level has:
    4s, 4p, 4d, 4f.

    The d shell consists of FIVE orbitals, each containing a maximum of 2 electrons (max of 10 electrons).
  9. Apr 17, 2005 #8
    ^^^ OHHHH so that's what's meant by it??? ok!! thanks!!

    dextercioby, here's what it says in the glossary:

    principal energy level(s): the main energy levels within the relectron arrangement in an atom. They are quantized by a set of integers beginning at n=1 for the lowest level, n=2 for the next, and so forth; also called the principal quantum number.

    so does that mean that the "principal quantum number/principal energy level" is the periods in the periodic table of elements??
  10. Apr 17, 2005 #9
    Yes, the period an element is in represents the valence energy level.
  11. Apr 17, 2005 #10


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    The adjective "principal" is used with energy levels because there is a small dependence of energy level on orbital angular momentum. That is why the sequence written earlier as
    [tex] 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 [/tex]
    is not strictly in the order 1, 2, 3, 4, 5. These small differences give rise to fine structure in atomic spectra.
  12. Apr 17, 2005 #11


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    There's no such thing as "main/principal" energy levels.There's only ENERGY LEVELS.

  13. Apr 18, 2005 #12
    I don't know about you folks, but this is what I was taught as vocabulary:


    For n = 6 (the 6th shell if you want to call it that way), l can range from 0 to 5, so for n = 6, the subshells are s,p,d,f,g,h. There are 5 d orbitals whenever the d-subshell is present for some n as whozum has correctly pointed out.

    The orbital orientations (dx, dy, dz, d(x^2-y^2),d(z^2)) are described by m (allowed to range from -l to +l including zero). If you know how the quantum numbers work you know which orbital "exists" for any energy level (whether or not it contains electrons is something different).
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