Re: Need help for painting the periodic table



Hop David schreef:
> I'm working on a painting based on the periodic table.
>
> ISTR from high school chemistry that elements wanted 8 electrons in
> their outer shell. Halogens with 7 electrons would tend to take an
> Alkali Metal's single outer electron.
>
> So are there 8 different kinds of elements?
>
> This is my tentative color scheme:
>
> Electrons
> in outer
> shell
> 1 blue
> 2 blue green
> 3 green
> 4 yellow
> 5 orange
> 6 orange-red
> 7 red
> 8 white
>
> What are elements 21 through 30? Should they have the same color as
> alkali earth metals (blue green) or should they be grouped with Boron,
> aluminum etc. (green)?
This set belongs to a whole separate class of elements, the so-called
transition elements (see below in my explanation).

>
> Do Fe, Ru, Os & Hs all have the same number of electrons in their outer
> shell? How about Sm & Pu (62 & 94)?
Just speaking of electrons in the outer shell is not relevant anymore
for these elements. The chemical and physical properties of these
elements also are strongly determined by electrons in deeper shells
(one deep or even two deep for the heavier elements).

>
> Thanks in advance for help or suggestions.
>
> Regards,
>
> --
> Hop David
> http://clowder.net/hop/index.html

The scheme for adding electrons with increasing element number is not
that simple.

For elements 1,2 it is simple. Electrons are added to the first shell.
For elements 3 .. 10 electrons are added to the second shell.
For elements 11 .. 18 electronsare added to the third shell.
Elements 19, 20 (K, Ca) add electrons to the fourth shell.

>>From this point, however things become more complicated.
Elements 21, 22, 23 add electrons to the *third* shell, which is one
shell below the outer shell.
Element 24 (Cr) adds *two* electrons to the third shell and *takes* one
from the fourth shell.
Element 25 adds one electron again to the fourth shell.
Eleements 26 up to 30 add electrons to the third shell again.
Elements 31 to 36 again are more well-behaved and add electrons to the
fourth shell.

Shells can have more than 8 electrons. The maximum number of electrons,
a shell can hold can be written as

SUM(2*(2*i-1)) for i from 1 to N inclusive, with N the shell
number.

For N=1 this gives 2, for N=2, this gives 8, for N=3, this gives 18 and
for N=4 this gives 32. Each value of i stands for a sub-shell, which
can contain 2*(2*i-1) electrons. The number of sub-shells in a shell
with number N equals N.

For the so-called transition elements, the lanthanoids and actinoids,
the pattern of adding electrons is more complex than for the other
elements and one cannot simply say that for each increment in the
element number an electron is added to a certain shell. Electrons can
be added to deeper shells, as shown by the examples above for elements
21 .. 30.

Whether an electron is added to the outer shell, one shell deeper or
even two shells deeper cannot simply be reasoned upon.
Quantum-mechanical computations show that e.g. for chromium (element
24) it is energetically more favorable to have only one electron in its
outer shell and hence, it adds, compared with elements 23 (vanadium)
two electrons to the deeper shell and takes one from the outer shell.
Why this is the case cannot be explained in simple layman terms,
quantum mechanics computations are needed to understand this.

Wilco

.

Relevant Pages

  • Re: S4E13 The Other Three Doctors, or Yer, right...
    ... >>>> Your use of shell instead of shells indicates that you obviously ... > about electron *shells* at all in relation to valency, ... The subject was about the quantum model of the atom which you are ... electrons form shells and subshells around it dictated by quantum theory. ...
    (rec.arts.drwho)
  • Re: S4E13 The Other Three Doctors, or Yer, right...
    ... It pulled atoms apart by neutralising the ... spare electrons" - i.e. the components of the atom are ... An atom only has one valence ...
    (rec.arts.drwho)
  • Re: nuclear shell model periodic table
    ... >> you know well that the shell model is far fome being something ... >> beside the croock club that you belong as well ... stupid shell model of electrons with the lanthanoid problem ... there is nothing about the geometric structre of the nuc ...
    (sci.physics)
  • Re: Why... (OT)
    ... sodium ions on nerve transmission. ... with electrons occupying a series of shells ... is building a model of an atom, one starts with the inner-most shell, ... outer shell electrons - thus leaving only the ...
    (uk.people.support.depression)
  • Re: Why... (OT)
    ... sodium ions on nerve transmission. ... with electrons occupying a series of shells ... Now, different atoms have different properties, and one of the most ... Each shell can only hold so many electrons, ...
    (uk.people.support.depression)