The Periodic Table Of Elements

The "Periodic Table Of Elements" is one of the most basic "texts" of not only practical chemistry but a philosophical statement about the substance from which all matter is created.

This page is my simplified explanation of what this "Table" is and why it is important.

I started this page by reading from "The Periodic Table, Its Story and its significance" by Eric R. Scerri, and will quote excerpts from that landmark work below. (click on the image for Amazon's listing of the book)

First it is a "table." That is, it is a written presentation of data arranged in some order. Here is a blank table -- a table is a structure that imposes some "order" or "pattern" to items placed IN the table.

The word "table" has many meanings. The meaning used here is the "box" above, not a "dining table."

You could have a table of courses you plan to take in college -- the table would contain such things as the names of the courses, the dates and times, the names of the professor, the classroom, perhaps the books that are necessary to take the course. All this information could be presented in a "table" and it could be called a "Table of Karl Loren's Courses at Ohio University for 1953."

You could have a "table" of weights for all your children, with any other data you wanted to add to your "table:"

The table is a structure of many "cells." There could be two rows or 350 rows. Each row could have one column or 30 columns, or there could be any other number for either rows or columns. At the intersection of one row and one column there is a "cell." The data in a "table" exists in "cells" and there are some cells which are on the same row, other cells that are in the same column. Generally both the row and the column have "significance" or a pattern. For instance in the "Weight Table of Persons" the rows have the significance that all the cells relate to one specific person. The columns all have a different significance -- the cells in the columns all relate to some characteristic about many different people (weight or day of birth).

The "order" or "pattern" is usually the distinctive character of the "table." The Weight Table of Persons is distinctive because it tells you the weight and the day of birth for various individuals.

You could have a "table of numbers from 1 to 100" or a table of names from "A to Z" or a table of types of cars from "Ford to Lincoln." This last characteristic of the "table" could be called the "name" of the table.

An Element Is Most Easily Identified With THE Atom that represents that element

A "table of elements" would include "elements" -- that term would have to be defined just as the term "names" would have to be defined for a "table of names." For the table of names the "names" term could be defined as "all the names in the Chicago phone book. Generally the definition of the "name" of the table is critical to be accurate and understandable.

For instance, one of the problems with the Table of elements is that it not all that easy to define "elements." That is one of the many problems with the "Periodic Table of Elements.

Another aspect of any table is the description of the pattern, or order of the data in the table. In the table of "names" the "order" is part of the name for the table. In other words, Table 3 is a table of names in reverse alphabetical order (based on the first name).

So, a table needs a definition of the terms or data placed in the cells and also a description or definition of the "pattern" or "order" for the data in the table.

The Periodic Table of Elements, clearly uses "elements" as the data to be placed in the table. This is not as straight forward as might seem likely.

"Hydrogen" for instance is one of the elements, as is "sulfur" but in fact "hydrogen" can exist with one electron around the atom or zero electrons. It has a different name for each state, but generally it is still considered "hydrogen."

However, for some chemists the differences between "elements" with one or two more or less electrons different from "normal" was considered so important that they had trouble agreeing on how to define an "element."

But if the definition of "element" caused controversy, the definition of "periodic" caused much more.

The regular pattern for a group of names is easy -- you could arrange them in alphabetical order, or you could arrange them first by sex (M or F) and then alphabetically, or in many other ways (first by city of birth, then by sex, then alphabetically by first name).

The most essential thing to know about the Periodic Table of Elements is that many different chemists and others have designed their own "order" or "pattern" in which to present the data.

The term "periodic" as used in the "Periodic Table of Elements" has usually meant the order based on the number of protons in the center of the atom of the substance. Since Hydrogen is an atom with ONE proton, it was assigned an "Order" of Atomic Number One.

Since Helium is an atom with TWO protons in the center of the atom, it was given the number of Atomic Number Two.

The chemist given most credit for creating the first Periodic Table of Elements was the Russian Dmitrii I. Mendeleev.

This is still the most simple and straightforward pattern for a "Periodic Table of Elements." A table listing the various elements according to their atomic numbers. But fancier tables were designed and are in use even now:

The periodic table

This table shows the various elements with different colors --- the colors portray an aspect of the pattern. For instance, you can see that some of the cells above are green, some are yellow. The green cells indicate that the element listed in that cell is called a "non metal" while the yellow cells are classified as the adjacent image displays: "Alkaline Earth Metals."

These terms, themselves, are more confusing than need be for this simplified presentation -- but the essence here is that some Chemists felt that whether an element was "acidic" in nature or "alkaline" in nature was so important that the Periodic Table of Elements should present that information as part of the pattern. "Other" tables of the same elements have other patterns -- depending on what characteristic of the element is considered most important for the purpose of that Table. There were more than 1000 different forms of the Periodic Table of Elements -- some now completely discarded by most scientists -- but all of which, at one time or another, were considered THE table by someone.

But some of the elements exist at normal temperatures as gases while others are liquids and some are solids. So, it might also be logical to develop a pattern based on which of these three states (gas, liquid or solid) is the usual state for this substance.

You might get into a controversy about substances which were either gas or liquid at different "normal" temperatures - and of course this was one of the problems with using the "gas/liquid/solid" pattern of data presentation.

In addition to definitions for the items placed in a table, and the description of the Pattern for the data, there could certainly be an "intended use" of the table that might become an important part of the table and affect the definition of data terms and/or the definition of the pattern.

For instance, a table of names might have a use considered extremely important by those who needed to pay for it or approve it -- let's say that intended use for the table of names was to detect what names were missing from various letters of the alphabet. Let's say that the table was for "last names" not for "first" names. What is the first letter of the last name of "Charley McCarthy?"

Right away you see that you would have to have some "rule" for how to define "last name" that would allow the intended use for the table.

Let's say you had a table with the sex of people, and there were names of "Jim" and "Jon." "Jon" could be a male or female name. "Jim is usually thought of as a name for a male.

The Book Of Rules -- Part Of Every Table

Right away you see that you would have to have another rule for how do you detect the sex by looking at the name -- or if this is impossible -- that the table now must have an independently found "sex" for the person.

The Periodic Table of Elements, based on the simple pattern of the number of protons in the atom (Atomic Number) was very useful. For one thing if some scientist discovered an atom (however he could do that) which had 23 protons and another atom that had 25 protons, AND if the general thinking was that there was probably an atom with every possible number of protons, from one to some higher number, then a logical scientist would look to see if any list of elements described an element with 24 protons in the atom.

Scientists working on the far fringes of science The Case Of The Missing Cherry

found atoms with various numbers of protons, and noticed that other atoms with smaller number of protons had not been discovered. So, the use of this table was considered so accurate that the guy discovering the substance with 25 protons could "announce" that he had discovered a "missing element" like a "missing cherry" but where there was clear evidence that it was missing -- the element with 24 protons! This was so useful that many otherwise unknown elements were discovered simply because some scientist found an atom with a number of protons NOT listed on the then-current Table of Elements.

This is a philosophical use of the Table -- and the table is considered a profound "philosophical statement" about chemistry -- as a "philosophical" statement is meant to mean true, but not based on direct observation -- more based on reason and logic, within a philosophical framework.

The "pattern" then began to get very fancy -- with the "table" presented in both rows and columns, like most "table" but where which row the element was in made a big difference.

In other words, all the elements might be listed in ONE row, from Atomic Number One though Atomic Number One Hundred (or whatever the current highest number was).

But if the first ten elements were all gases (which they are not) and the next 20 elements were all liquids (which is also not true) and all the rest were solid (not true, either), then the table could be logically presented as having three rows, one for gas, one for liquids and one for solids.

The clever scientists son discovered that there were elements that had very low atomic numbers -- the same range of numbers as the gasses, but these were liquids, and that there even some solids mixed in amongst the liquids if the only pattern were atomic number. Thus a "new" Periodic Table would be announced from time to time, then the pattern of THAT table was found to not fit all the observed data, so the pattern would be modified or thrown out.

Clever chemists gained more and more confidence that this table could be successfully used to predict chemical properties such as what chemical would combine easily with what other chemical.

How about Aluminum and Arsenic? Well, I couldn't find that as a chemical compound. Perhaps I just missed it. If I understood the Periodic Table better I could look at it and see whether aluminum and arsenic were capable of bonding -- since "bonding" is one of the characteristics that can be gleaned from the Table.

If you have read all the above carefully, and understand it -- you understand more about the Periodic Table of Elements than 99% of people. Congratulations.

But you would still only be understanding less than 1% of what the table can teach you!

Dr. Scerri's excellent Book goes on to describe many others of the pieces of the patterns shown in this remarkable table. I won't try to explain lots of those here, but there was one pattern that was discovered that came to use the name "triad."

"Triads" were discovered even before the periodic table was in any full form. "Triads" simply meant a group of three chemicals as shown in a list in the order of "atomic weights" (similar to atomic number) that had similarities.

The interesting significance of triads is that with more insight, and according to Dr. Scerri

A "vertical triad" consists three elements that are in the same vertical column of the Table -=- such as Oxygen (Atomic 8) - Sulfur (Atomic 16) - Germanium (Atomic 32). It appears that sulfur and germanium relate very much to oxygen in very unique ways -- they enable oxygen to be transported across the membrane of a cell -- thus allowing health of the cell, health and multiplication of the stem cells and regeneration.

This "vertical triad" shows up in the original Periodic Table, designed by the originator, Mendeleev, who put GERMANIUM, atomic number 32, under sulfur and oxygen in the same column even though it had not yet been discovered. In fact this is one of the brillant things about the original table -- it allowed the prediction of characteristics of various elements, even those that had not yet been discovered.

Others, since then, have had other fish to fry and shifted some of the elements so that germanium was no longer directly under sulfur. I will not assert the wrongness or rightness of such shifts in basic truth, but comment that there was an original form of the Table and there are other forms.

Since the Biosulf applies to the whole body, there is no localization of effect other than what priority the DNA of the body places on any one part for regeneration. The whole of the body has the goal of infinite life, never to succeed, but in the process, the Master Blueprint, the DNA will allow sacrifice of some parts for the more important survival of other parts.

In the mid-1800s, most chemists worldwide were convinced that the elements existed in families that had similar physical and chemical properties. However, there was no widely accepted chart that explained relationships in chemical properties among chemical groups. The periodic table, an information organizing tool that we take for granted today, began as a simple question in the mind of a Russian scientist, Dmitrii I. Mendeleev (1843-1907). What is the relationship of the elements to one another and to the chemical families to which they belong?

Mendeleev's passion for understanding the families of elements took him into previously uncharted territory. He felt that the newly understood atomic mass measurements would have greater significance once scientists clearly understood the relationships among the elements. Mendeleev wrote his ideas into the chemistry textbooks from which he taught.

In Principles of Chemistry, published in 1869, Mendeleev introduced a concept he called the Periodic Law that stated:

He subsequently published several versions of a periodic table of the elements, including all elements known at that time. How was Mendeleev able to chart the relationships among the 63 known elements? It all started in a game of cards.

In order to understand the properties of the known elements and their relationships to one another, Mendeleev developed a card game. He wrote out the properties of each element on a different card and spent a great deal of time arranging and rearranging them. He was looking for patterns or trends in the data on the cards. His friends called this game “Patience.”

Mendeleev first arranged all the cards from lowest to highest atomic mass. The lightest element known in Mendeleev’s time was hydrogen. Its properties were not like any other known element. So Mendeleev decided to leave it out of his game.

Scientists who are initially struggling to understand a large mass of data commonly ignore, at least for a time, those data points that seem too different from the others. These unusual instances are termed outliers. Whether or not outliers can eventually be explained by a model often makes or breaks the scientific theory from which the model derives.
The second lightest element known to Mendeleev was lithium.

We now know that the second lightest element, between hydrogen and lithium, is helium. But helium was not discovered on earth until 1895.

So Mendeleev started his game with the element lithium. In order of increasing atomic mass, Mendeleev thought about the elements beryllium, boron, carbon, nitrogen, oxygen, and fluorine. These elements were all different in their physical and chemical properties, thus seeming to belong to different families. Mendeleev put their cards in a vertical row, with lithium at the top and fluorine at the bottom.

The known element next most massive after fluorine was sodium. It shared many physical and
chemical properties with lithium. They seemed enough alike to be classified as belonging to
the same family. Thus Mendeleev put sodium’s card as the top of a second column, just to the
right of lithium’s card. From there things worked amazingly well. Mendeleev was thinking about the similar properties of the next elements.

Magnesium, following sodium, had physical and chemical properties similar to beryllium, which followed lithium. In the same manner, Mendeleev placed aluminum next to boron; silicon next to carbon; phosphorus next to nitrogen; sulfur next to oxygen; and chlorine next to fluorine.
Mendeleev must have felt great pleasure in how this card game was turning out. Repeating patterns are called periodic.

Mendeleev eventually called this arrangement the periodic table of the elements.

Mendeleev encountered the first problem with his model in the next set of elements.

Potassium headed the third column, since its properties were similar to those of sodium
and lithium. Calcium was next, and it fit well with magnesium and beryllium. The next known element was titanium. According to Mendeleev’s model, it should have belonged to the same chemical family as boron and aluminum. But titanium’s properties were similar to those of silicon.

Mendeleev did not give up. He decided to put titanium in the row with carbon and silicon. He left a
gap next to boron and aluminum.

* Mendeleev did not know the identity of the elements that would be placed in these cells, but he knew they must exist and he predicted not only their discovery, but their chemical characteristics based on the elements to the left in the same rows. Germanium, fully predicted by Mendeleev, was later discovered to be on the same row as oxygen and sulfur and to have the exact chemical characteristics predicted by Mendeleev.

He predicted that an unknown element would some day be found with an atomic mass between 40 (for calcium) and 48 (for titanium), whose properties would be similar to those of boron and aluminum.

In fact, in 1878 the element scandium was discovered. Its atomic mass was almost
45, and it had properties as predicted by Mendeleev.

Later Germanium was discovered, given the name of Atomic Number 32, on the same row as oxygen and sulfur.

Mendeleev continued laying down his cards and felt comfortable identifying two more gaps or “missing” elements in the fourth column, in the third and fourth rows. His genius is shown in his ability to recognize the potential for missing data and to use existing data to predict the properties of these unknown elements. Mendeleev left spaces on his periodic tables because he did not "force" the known elements to fit any preconceived pattern. The absence of elements with certain physical and chemical properties also indicated that not all existing elements had yet been discovered.

Mendeleev interpolated from what he knew to make predictions about what was missing. These predictions guided the search for other elements.

Mendeleev not only suggested that elements similar to aluminum and silicon should exist. He predicted several properties of "ekasilicon". “Eka” means “first,” “beyond,” or “after” in Greek.

Mendeleev thought ekasilicon would have a specific gravity of 5.5, and its oxide would have a specific gravity of 4.7. He was right on both counts. These values are close to those eventually found for germanium. Gallium (similar to aluminum) and germanium (similar to silicon) were discovered in 1871 and 1886, respectively.

Mendeleev focused on the chemical properties of the elements. He concluded that certain commonly accepted values for atomic masses were incorrect. He calculated that the atomic mass of chromium would be greater than the value being used at that time. Although there was a place in the table for chromium between calcium and titanium based on the incorrect value for its atomic weight, the properties of chromium did not fit with this placement.

By 1871 , Mendeleev had modified and improved his first periodic table of the elements. He used its organization of information to predict the existence of ten elements (now known as Sc, Ga, Ge, Tc, Re, Po, Fr , Ac, and Pa) . He fully described in great detail four of these ( Sc, Ga, Ge, and Po). He did this by interpolating information from what was known.

Mendeleev became world famous because of his development of the periodic table of the elements. He traveled throughout Europe, visiting with other famous scientists. However, Mendeleev was a political liberal. Czar Alexander II, who ruled Russia in the late 1800s, did not approve of Mendeleev. Therefore, Mendeleev was never recognized by being elected to the Russian Academy of Sciences. However, Mendeleev was honored posthumously in
1955 when Mendelevium, manmade element number 101 in the modern periodic table, was
named for him.

Because sulfur is directly below oxygen in the periodic table, these elements have similar electron configurations. As a result, sulfur forms many compounds that are analogs of oxygen compounds, as shown in the table below. Examples in this table show how the prefix thio- can be used to indicate compounds in which sulfur replaces an oxygen atom. The thiocyanate (SCN-) ion, for instance, is the sulfur-containing analog of the cyanate (OCN-) ion.

Oxygen Compounds		Sulfur Compounds
Na2O (sodium oxide)		Na2S (sodium sulfide)
H2O (water)		H2S (hydrogen sulfide)
O3 (ozone)		SO2 (sulfur dioxide)
CO2 (carbon dioxide)		CS2 (carbon disulfide)
OCN- (cyanate)		SCN- (thiocyanate)
OC(NH2)2 (urea)		SC(NH2)2 (thiourea)

The Periodic Table Of Elements

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The periodic table