why did dimtri arrange the table like that?

Question

why did dimtri mendeleev arrange the periodic table of elements the way he did.

Answer 1

He didn't arrange them in order of atomic number, as the modern table does, since that concept wasn't yet known. The various pieces of the atom; protons, neutrons, and electrons, had yet to be discovered.

He arranged them in order of atomic weight, which was known. If you do that very simply you get one long line. His genius was to look at chemical properties and break the long line into segments, which he stood up on end next to one another, so that elements with similar chemical properties were next to one another. The result was something like the modern periodic table placed on its' side. Here's his early table:

http://web.lemoyne.edu/~giunta/EA/MENDELEEVann.HTML

In a couple of instances he broke the rule about using atomic weight to get elements with similar chemical properties in the right place. He thought that the determination of those weights must have been wrong (note the question mark next to the atomic weight of tellurium in the table pictured above). In fact the periodic table does order itself by atomic number, not weight, and there are a very few cases where atomic weight decreases as you go up in atomic number, like tellurium/iodine.

More info:

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

And a good book about It:

http://www.amazon.com/Mendeleyevs-Dream-Elements-Paul-Strathern/dp/0312262043/sr=1-1/qid=1167715668/ref=pd_bbs_1/104-7855031-2575151?ie=UTF8&s=books

Answer 2

The columns of the periodic table were put together so that each column had elements with similar properties. For example, the last column, starting with helium, are all gases which do not react with any element in any chemical reaction. Dimitri and others new about atomic number, but what Dimitri's insight was was that chemical properties were "periodic" as you went through the elements. Thus he arranged the table in such a way to reflect this.

What is truly amazing is how accurately the periodic chart illustrates electron configurations, something not discovered until many years later, as well as the table's prediction of certain elements which had yet to be discovered.

Answer 3

Mendeleev arranged the elements in that order by their atomic number (number of protons existing in and atom of that element) and by their groups (or families). The groups were made up of certain properties that the elements share. They were also split up by whether they were halogens, noble gases, alkali metals, alkali earth metals, transition metals, etc. Mendeleev, actually, did not originally design the table as it is today. His version is read vertically instead of horizontally. Over time, the periodic table has changed, and if you put all the pieces of the puzzle together, then the table all makes perfect sense!

Answer 4

Who is dimtri, why is he arranging the table, who is it set for? You are new to this but you gotta think about your question before you submit.

Answer 5

urm, like how?