Atomic density

[Peabrain]

Which substances have the highest atomic density and what does it mean?

[gen2]

Atomic density means the number of atoms per unit volume.

Solids will have the highest atomic density and gases the least.

Also you can get more small atoms into any given space than large ones. Under normal conditions, that should mean that lithium has the highest atomic density.

[Peabrain]

Thanks gen2, I had been told that diamond had the highest atomic density is that likely?

[gen2]

Yes Peabrain, that is most likely. I couldn't find a value for the atomic density of lithium so that is why I only stated that it "should have".

Carbon is on the same row of the periodic table and all the atoms on that row have fairly similar atomic radii. Carbon has an atomic density of 1.14 x 10^23. Diamond has a much higher atomic density of 1.77 x 10^23.

I also qualified my answer with the phrase "Under normal conditions" and of course graphite is the stable state of carbon at STP. Diamond requires high temperature and pressure conditions to be formed and is theoretically unstable at STP but fortunately for all ladies out there, the activation energy required to initiate the change from diamond to graphite is higher than is likely to be encountered under normal circumstances.

[jake-the-peg]

incidently I have seen a rather expensive piece of film of a diamond being burnt in liquid oxygen!

Aggregated diamond nanorods are apparently 0.3% denser than diamond

http://en.wikipedia.org/wiki/Aggregated_diamon d_nanorods

But that's a pretty esoteric substance