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Question about the periodic table arrangement

  1. Mar 17, 2015 #1
    Hi, I'm new here.

    I'm actually studying the periodic table and while collectting the data on excel i noticed something. I wouldn't see it with the usual display of a periodic table but when you put it all in a sheet, ligns after ligns it become obvious to me.

    Argon Ar (noble gaz) is followed by Potassium K (Alkali metal) and then Calcium Ca (Alkaline earth metal)

    Same goes for H, Li, Br or Ne, Na, Mg or Kr, Rb, Sr or Xe, Cs, Ba or Rn, Fr, Ra

    so a noble gas is followed by an alkali metal then an alkaline earth metal.

    Why ?
     
  2. jcsd
  3. Mar 17, 2015 #2

    Quantum Defect

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    This is the essence of the periodicity that Mendeleev noticed: elements with similar chemical properties repeat cyclically.

    Later, quantum mechanics helped to explain the observed periodicity by describing the way that electrons get added to atoms (orbitals and the Aufbau principle).
     
  4. Mar 17, 2015 #3

    SteamKing

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    There's a certain organization to the periodic table.

    http://en.wikipedia.org/wiki/Periodic_table

    The columns in the table are called groups, and the elements in each group have similar electron configurations in the outer shell. Thus, all the elements with only one electron in the outer shell are in Group 1 and are all metals except for hydrogen. All the noble gases are in Group 18, at the other end of the table, and each of these gases has a full complement of electrons in its outer shell. If you take the next element after neon (atomic number 10), for example, that additional electron can't fit into the outermost shell for neon; it must go into its own shell, thus sodium (atomic number 11), an alkali metal.

    It's called a "periodic" table because these properties and relationships repeat after progressing thru a certain number of elements. This was the great insight of Mendeleev, who published the first periodic table.
     
  5. Mar 17, 2015 #4
    so it's not related to elemental transition ? simply an indication that the number of electron is close ?
     
  6. Mar 17, 2015 #5

    Quantum Defect

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    scientists believe: Elements have similar chemical properties because their electron configurations are similar. Ne: [He]2s^2 2p^6; Ar: [Ne]3s^2 3p^6, etc. The outermost electrons are ns^2 np^6.
     
  7. Mar 17, 2015 #6
    if i get it right, the element 119 (Uuo) would be followed by a (yet unknown) Alkali metal ?
     
  8. Mar 17, 2015 #7

    SteamKing

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    Could be. Most tables only go up to element 118 (which should be a noble gas).
     
  9. Mar 17, 2015 #8

    SteamKing

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    It's not clear what these two statements mean. What sort of transition? The number of electrons is close to what?
     
  10. Mar 17, 2015 #9
    i'm working on a star system generator on excel, for RPG purpose.

    So i'm now studying nucleosynthesis to know how a star work so that my generator is able to provide the composition of a star (or a planet athmosphere or crust, or whater)

    Now i'm on the stellar part and i'm trying to understand how nucleosyntheisis works. It start with hydrogen (or helium?) and then goes throught many transition before it end up being Iron (if i understood correctly)

    that is the process i'm tryingto understand and that's why i ended up studying the periodic table.
     
  11. Mar 17, 2015 #10

    SteamKing

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    Well, nucleosynthesis is a little more complicated than you have described. The Periodic Table was developed primarily for chemists; in order to understand nucleosynthesis, you need to know something about atomic physics rather than chemistry:

    http://en.wikipedia.org/wiki/Nucleosynthesis
     
  12. Mar 17, 2015 #11
    "Well, nucleosynthesis is a little more complicated than you have described."

    yeah i know :)

    I'm still struggling to understand it. i've got a very basic idea of what it is.
     
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