Why are compounds no in the periodic table?

Answer 1

only pure atoms are on the Periodic Table, a compound is a combination of two or more elements chemically bonded to each other, so in short compounds are not on the periodic table because they could be sodium chloride, not an element, it is a molecule, you catch my drift?

Answer 2

There are over 20 million known compounds. There are over 100 billion possible compounds containing only H, C, O and N. It would be huge.

One major reason is the periodicity of the elements. You can line the elements up into neat functional groups - alkali metals, transition elements, halogens, etc. This you couldn't do with compounds, even if you had a separate table for hydrocarbons, one for elastomers, one for dyestuffs... Compounds also find wide use as smaller blocks of larger compounds. We call these precursors. Take toluene. It's a very toxic compound, but if you compound it into toluene diisocyanate, then compound that into polyurethane, it becomes safe enough that you can build it into replacement hip joints. Chemists do keep books of compounds, but a table on a big sheet of paper the size the entire side of a supermarket? It could never happen.

This would be an impossible task/table as there are literally tens of millions of compounds, and new compounds are being created or developed all the time. For an idea of how many compounds there are, have a look at an Aldrich catalogue, which you'll find in most labs.

Why should there be a periodic table of compounds? People used to have no idea how chemicals worked. Then they got an inkling that everything may be made of atoms. They then began to study elements (types of atoms) by experimenting on the elements themselves, and on their compounds. It was only then, in the 19th century, that people like Mendeleyev spotted patterns in the way the elements acted and reacted. Today, we know why this pattern exists. In fact, we now have a pretty good understanding of how chemistry works. If there had been some nice table we could put all compounds into, we would have put one together by now.

Answer 3

Compounds are not on the periodic table, because they are made out of elements. While elements are particle that are a 100% pure, at least in non-lab settings. There are thousands of compounds out there compared to a handful of elements, that is why compounds are not shown. Hope this helps.

Answer 4

There are only a few dozen elements, which can easily be listed in a simple table.

There are millions of compounds which could not be easily fit into a single table.

Answer 5

The Periodic Table's full name is the Periodic Table of Elements, which makes it pretty self-explanatory that it has only elements.