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Harmonic Relationships


hazelm

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In DK's book "The Philosophy Book is written this:

 

In 1865, English chemist John Newlands discovered that when the chemical elements are arranged according to atomic weight, those with similar properties occur at every eighth element, like notes of music.  (underscore mine).

 

What are these "properties"?  Can someone please give me an example?  Thank   you.

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"

 

John Newlands did not discover the periodic table

-- the periodic table was not "out there" to be discovered. It did not exist until Mendeleev published a form of it in 1869.

-- John Newlands devised a classification scheme for the elements in 1863-65, which he called the "law of octaves". The basis for the classification was quite similar to the "periodic law" which led to Mendeleev's classification scheme.

 

-- In his 1863 scheme John Newlands successfully arranged about 20 elements, roughly one third of the then known elements, into families, on the basis of atomic weight. Every seventh element had generally similar chemical properties.

--Possibly responding to criticism about the relatively small number of elements in the arrangement, he prepared a similar scheme with all of the then known elements included for an 1865 presentation to the London Chemical Society.

 

-- This was, in effect, "laughed out of court" by the leading British chemists of the day because (i) Some of the family relationships in his scheme were rather ludicrous (ii) he had (unfortunately) suggested a parallel with the 7-note musical scale, which they saw as ridiculous (iii) he had left no gaps to accommodate new elements at a time when new elements were being discovered at a rate of approx. one each two years.

"

http://www.answers.com/Q/How_did_john_newlands_discover_the_periodic_table

I agree.  I do not think I said he discovered the table.  He discovered the "law of octaves".  And, in a way, he did not really discover that.  Musicians had already learned that the first note of a scale and its ending note are companiable.  ("companiable"?  Is that a word?)  Anyway, pleasant to the ear.  Not all notes can be paired and have a pleasing sound.  In the case of music,  the sound is the property.  What is it in the  elements?  Can you select one pair of first and eighth elements that does have specific properties to be seen and named?  I am not challenging the idea on that basis.  I just want to know what I am looking for.

 

And - "7 note scale"?

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I agree.  I do not think I said he discovered the table.  He discovered the "law of octaves".  And, in a way, he did not really discover that.  Musicians had already learned that the first note of a scale and its ending note are companiable.  ("companiable"?  Is that a word?)  Anyway, pleasant to the ear.  Not all notes can be paired and have a pleasing sound.  In the case of music,  the sound is the property.  What is it in the  elements?  Can you select one pair of first and eighth elements that does have specific properties to be seen and named?  I am not challenging the idea on that basis.  I just want to know what I am looking for.

 

And - "7 note scale"?

A seven note scale is what the regular major and minor scales really are, given that the 8th note is the start of the next octave. Whereas Newland's law of octaves really is a series of 8, with the start of the next series being the ninth. 

 

It turns out that the "law of octaves" is after all a harmonic relationship, since each short period of the Periodic Table represents the start of a new harmonic series of electron orbitals. (Orbitals, being wavelike, correspond quite closely to "spherical harmonics", i.e. the modes of resonant vibration of a rubber ball: https://en.wikipedia.org/wiki/Spherical_harmonics )  

 

However he was only partly right, since the harmonic series in successive "octaves" is actually more complicated, going like this:

1) 2

2) 2+6 = 8

3) 2+6+10 = 18

4) 2+6+10+18=26

etc. 

But, leaving aside hydrogen and helium as special cases,  for the first two short periods of the periodic table, one has elements which are climbing up the "scale" of the the 2+6 parts of periods 2 and 3. So you seem to have two "octaves", until you take into account the heavier elements in the transition metals, which are where the 10 in the 3rd series comes into play for the first time.  And after that the octave idea doesn't work any more of course for the heaver elements. But schoolchildren today still learn the "octet rule" for light elements, which is the direct descendent of Newland's idea.

 

(These elements in the first 2 short periods are mostly common ones that had well-researched chemistry in Newland's day: Li, Be, B, C, N, O F, Ne; Na, Mg, Al, Si, P, S, Cl, Ar.)   

Edited by exchemist
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I agree.  I do not think I said he discovered the table.  He discovered the "law of octaves".  And, in a way, he did not really discover that.  Musicians had already learned that the first note of a scale and its ending note are companiable.  ("companiable"?  Is that a word?)  Anyway, pleasant to the ear.  Not all notes can be paired and have a pleasing sound.  In the case of music,  the sound is the property.  What is it in the  elements?  Can you select one pair of first and eighth elements that does have specific properties to be seen and named?  I am not challenging the idea on that basis.  I just want to know what I am looking for.

 

And - "7 note scale"?

Now, regarding the similar properties in the first two short periods, here are some examples:

 

Li, Na: very reactive metals, forming ions with a single +ve charge

 

Be, Mg:  reactive metals forming ions with a double +ve charge

 

B, Al: B is a semimetal forming 3 bonds, Al is a metal forming ions with a triple +ve charge

 

C,Si: C is a non-metal forming 4 bonds, Si is a semimetal forming 4 bonds

 

N, P: N is a gas forming 3 bonds, P non-metal forming 3 or 5 bonds

 

O, S: O is a gas forming 2 bonds or ions with double -ve charge, S non-metal forming 2,4 or 6 bonds or ion with double -ve charge

 

F, Cl: both pungent reactive gases with yellow-green colour forming one bond or ion with single -ve charge

 

Ne, Ar: "noble"or "inert" gases, extremely unreactive, with almost no chemical reactions at all.  

 

As you can see there are plenty of big differences as well as similarities, but the similarities are sufficiently marked to be useful as an organising pattern or principle. It was only with the much later advent of quantum theory that the basis of these similarities could be properly understood, as being due to the numbers of electrons in the atoms of each element and which orbitals they occupy.

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All right.  Now I see why I  could not catch the properties.  Thank you for that.

 

Even the patterns are not what I was envisioning.  I think I'll tackle those first because I suspect I know what was wrong.  I was trying to use the current table.  But there have been new and intervening elements found since Newlands' time. Neon?  I need to use Newlands' own table which I found later. 

 

That in part and partly this:  (Quote from yours)  "A seven note scale is what the regular major and minor scales really are, given that the 8th note is the start of the next octave. Whereas Newland's law of octaves really is a series of 8, with the start of the next series being the ninth."  I need to go back to school.  I am almost sure our octave was a series of eight with the higher simply serving as the end of one and the beginning of the next.  Wish my trombone-playing ex-neighbor still lived here.

 

Thank you very much.  Thank you both.  Now I can move on.  Or, back up?

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In the Left Step Periodic Table devised by then elderly French polymath Charles Janet in the late 1920's, new orbitals are introduced in order, so 1s, 2s, 2p3s, 3p4s, 3d4p5s, 4d5p6s, 4f5d6p7s, 5f6d7p (and 8s should we ever synthesize atomic numbers 119, 120). Thus the right edge elements are always s-block elements.

 

s=2, ps=8, dps=18, fdps=32, and so forth, all half-squares or doubled squares according to taste.  The Left Step system is far more 'harmonic' than the currently popular table where periods end with noble gases (which aren't homogeneous, since helium is s2 while all the other nobles are p6).

 

Paired periods of same length are referred to historically as 'duals'. Their total constituencies are square numbers of elements.  So summing them leads to tetrahedral numbers as atomic numbers for every other s2 element within the Janet system. 

 

Jess Tauber

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I have a wooden sign over the kitchen sink that reads "When in doubt, add more wine".  My wife has never had a drop of alcohol in her life, but the wine definitely helps (me).

When I had Windows and had to call Dell,  I always - absolutely always - had a glass of wine first.  I knew the agony that was coming.  Partly my stupidity and greatly their annoyance with me. 

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