I've got an assignment to do for chemistry, and it's the history of the periodic table, and I've got quite far on it, but I'm stuck on the similarities and differences.

 

For similarities I have that they're separated into rows and columns, and are arranged by atomic weight, and for differences I have that the original table didnt have groups or periods, the lanthanoid and actinoid series werent there, and that the elements werent categorised so specifically.

 

But now i'm stuck

 

So I was just wondering if anyone could give me a hand with the similarites and differences, because I really can't think of any more .

 

Thanks.

they split on a Macro level into metals and Non-metals for a start.

 

group 1, are the Alkaline metals, group 2 are the alkaline Earth Metals (and give some pretty good colors in Pyrotechnics).

then you have the D block (Transition Metals) quite a few give nice colors in certain oxidation states (they can have more than one).

group 3 has a non metal but all the others there have quite low melting points.

group 7 are the Halogens. and group 8 are the noble gases (sometimes called the Inert gases).

 

that`s about as General a breakdown as it gets

Plus, most of the heavier metals (above 92) weren't discovered until various degrees of recently.

Thanks for that, but it isn't what I asked for.

 

Plus, most of the heavier metals (above 92) weren't discovered until various degrees of recently.

 

Oh, Thanks