Chemistry Engineering Question:

One major reason I can think of, that has not been addressed yet, is the periodicity of the elements. You can line the elements up into neat functional groups--alkali metals, transition elements, halogens and so on. This you could not do with compounds, even if you had a separate table for hydrocarbons, one for elastomers, and one for dyestuffs... Compounds also find wide use as smaller blocks of larger compounds. We call these precursors. Take toluene. It is 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 of...oh, the entire side of a Wal-Mart store might be big enough? It could never happen.