Mendeleev on Periodic Table Formulation

[Vts]

I was surprised to read in Dmitri Mendeleev's 'The Relations between the Properties of Elements and Their Atomic Weights':

'...every (periodic) system, however, that is based upon exactly observed numbers is to be preferred of course to other systems not based upon numbers because then only little margin is left to arbitrariness... Properties, such as the optical and even the electrical or magnetic ones, cannot serve as basis for the system naturally, since one and the same body, according to the state in which it happens to be at the moment, may show enormous differences in this regard.'

 

Wait a minute, today's standard IUPAC Periodic Table does not follow that rule in regard to the quantum numbers, which are the most exact numbers by definition. Traditional Periodic Table, by separating metals from non metals, completely ignores quantum numbers n, l, ml and ms, which define electronic configurations of the atoms, which, in turn, define the nature of the elements. What if we bring the traditional Periodic Table in conformance with the quantum numbers as in ADOMAH Periodic Table http://www.meta-synthesis.com/webbook/35_pt/pt.html#perfect ?

Blocks of the Periodic Table (fdps) become equally spaced slices of the regular tetrahedron!

Bravo, Dmitri Mendeleev!

[insane_alien]

Traditional Periodic Table, by separating metals from non metals, completely ignores quantum numbers n, l, ml and ms, which define electronic configurations of the atoms, which, in turn, define the nature of the elements.

 

actually, the periodic table DOES take this into account, there are the s, p, d and f blocks on the table.

 

the s block is the alkali metals and earth alkali metals. both these elements have an s orbital valence shell.

 

the p block is also known as the main group which all have p orbital valence shells and the d block or transition metals all have d orbital valence shells

 

same applies with the f block. also known as the lanthanides and actinides.

[Vts]

actually, the periodic table DOES take this into account, there are the s, p, d and f blocks on the table..

 

The spdf blocks ( that reflect only quantum number l) are visible in the IUPAC Periodic Table and principal quantum number n is followed only for the first three periods, but traditional Periodic Table is not built in order of the quantum numbers. Even spdf blocks are not in the correct order. Left Step PT is built in order of quantum numbers l and in accordance with n+l rule. ADOMAH PT is the only periodic table that is ordered in accordance with all four quantum numbers. It naturally folds into the regular tetrahedron, which is quite remarkable.

[insane_alien]

you do know that good old dimitri developed the table BEFORE quantum mechanics. he was not reffering to the quantum numbers. he was reffering to atomic numbers. they are also grouped by valence shell electron numbers.

 

in its current form, it is useful, we can even predict properties of elements before they are discovered, there is lots of stuff you can use its current form for.

 

as for the one you link to, i see no real use for it.

[Daecon]

It's funny how the periodic table can be more-or-less arranged into a two-dimensional grid or rows and columns. It would have been more interesting, I think, if a more logical/physical form of the periodic table was a three-dimensional grid, with elements along each axis having something in common with it's neighbours in each direction.

 

But then, I'm not the Universe.

[Vts]

you do know that good old dimitri developed the table BEFORE quantum mechanics. he was not reffering to the quantum numbers. he was reffering to atomic numbers. they are also grouped by valence shell electron numbers.

 

Do you mean atomic weights? I do not think that he even knew about the atomic numbers at that time. He used what he had. But if he had known about the quantum numbers, which are certainly the "exact numbers", wouldn't he come up with a formulation that reflects them in some way? I bet he would look into that.

[insane_alien]

if they knew about atomic weights then they knew about atomic numbers. the first tables were done by weights but this lead to anomalies so it was switched to atomic numbers. this lead to a more functional table.

[thedarkshade]

the first tables were done by weights but this lead to anomalies so it was switched to atomic numbers.

When the periodic system was first set this was based on atomic mass, but there were some disorders, like elements with bigger atomic mass were placed before those with smaller mass, and Mendeleev couldn't explain this why. It wasn't really like he missed anything but that those disorders were due to isotopes, a term with back then was unknown.

[Vts]

If you list the elements by the atomic numbers or weights only it would be single continuous line or column of the elements. We know now that periodicity is based on n+l rule, aufbau principle, Hund's rule and Pauli Exclusion principle. All of the above, as well as chemical and physical properties, ultimately connected to the electronic configurations, which are described by the quantum numbers n, l, ml and ms.

 

Why not the Periodic Table? If Periodic Table is based strictly on the quantum numbers, perhaps some mysterious chemical relationships could be solved.

[Vts]

Just read an article that Element 114 (Uuq) does not behave as a metal at all, but rather as a nobel gas! That is another confirmation that the Periodic table has to be based on the Quantum Numbers and not on the chemical properties.

[insane_alien]

care to tell us the article? i'd be interested to read it.

[Vts]

Yes. That is Science News, April 12, 2008 issue. Vol. 173, No. 15., p.230.

Title: " Einstein's Invisible Hand. Is relativity making metal act like a noble gas?"

[iNow]

Yes. That is Science News, April 12, 2008 issue. Vol. 173, No. 15., p.230.

Title: " Einstein's Invisible Hand. Is relativity making metal act like a noble gas?"

 

http://www.sciencenews.org/articles/20080412/fob6.asp