Is the periodic table finite?

Four new elements named today, numbers 113, 115, 117 and 118.

Could the table be added to ad infinitum or is there a limit to the number of elements that can be created? (Apologies if this is a dumb question, my scientific literacy is not of the highest.)

There is belief there is an upper bound due to electrons needing to go light speed to stay in so-called “orbit”.

And nuclear considerations in which beyond a certain point a nucleus would “drip” neutrons and protons. We don’t know exactly how high the absolute limit is but we’re confident there is one.

How high up the chart is Vibranium? Probably no higher than that.

Some scientists think the periodic table can be extended indefinitely, the majority think there is a limit. Generally the limit is though to be either shortly after the island of stability centered around 126 or at element 173 where there is some weirdness with binding energy that I don’t quite get. AFAIK there isn’t a definite answer, just computer modeling of possible behavior that might or might not be accurate.

If you limit you definition of “nucleus” to collections of nucleons held together with the residual strong force, then there (probably) is a limit. If you extend that to collections of nucleons held together by other forces, then neutron stars break that limit (but introduce a new limit at which you get a black hole instead of a nucleus).

Hmm, given that the op was about the periodic table and the periodic table is about chemical properties, and I’d assume the larger nuclei would have rules about how they interact with other nuclei and electrons, I’d say it qualifies.

Geez, I never thought of that. Is a neutron star as “dense” as a nucleus (if that is a meaningful question)? Is it surrounded by really big electron clouds?


Roughly the same density. Most of the electrons have merged with protons to form the neutrons.

As far as the OP goes, now we have a new meaning for “Og smash” (Og being element 118).

Electrons are not in satellite-like circular orbits based on things like speed and gravity.

Rather electrons exist in atomic orbitals which is a 3D probability distribution in the vicinity of the nucleus. Each electron energy state is not a thin spherical shell but a different shaped 3D probability cloud. The below diagrams illustrate different electron orbital energy states. The brighter-shaded regions have greater probability of the electron being there.

Here is a visualization utility to illustrate this. It is an old Win32 app called Orbital Viewer. I just tested it on Windows 10 and it seems to still work:

Even the high-end currently-known nuclei can’t really be said to have any meaningful, “chemistry”, being created in such small quantities and having such short lifetimes. Has Oganesson ever even existed in a non-ionized state?

Yeah…but if a nucleus happened to be, say, a mile wide, the electron would not be able to distribute itself over that “orbital.” The limitation was phrased in Newtonian terms, but it still applies.

The periodic table is absolutely “finite” because the alternative is that it’s infinite, and I guaran-damn-tee you nobody is ever going to synthesize element Googleplex-factorial.

All of these super-heavy elements are already past the end of the periodic table, and there is no end to the periodic table.

I guess I’d better elaborate on that. Fundamentally, the Periodic Table is about electrons. More specifically, it’s about the behavior of electrons in the vicinity of compact particles of various positive charges. When we say that carbon and silicon behave similarly, for example (as illustrated by them being in the same column of the table), what we mean is that the electrons in the vicinity of a +6 charge behave in a similar way to electrons in the vicinity of a +14 charge.

Now, there’s no inherent reason why those compact positive charges need to be clumps of protons and neutrons. Those are the only sorts of compact charged particles of significant charge we know of, but it’s conceivable that you might also be able to make such from quark nuggets, or microscopic black holes, or some other construction. And if you had a quark nugget or whatever with a charge of +6, and gave it six electrons, then you’d have something that would behave in nearly the same way as carbon. In fact, one might justifiably even say that it is carbon. And similarly, if you had such a compact particle with a charge of +92 or +118 or whatever, you could put electrons around them and make weird versions of uranium or oganesson. So long as you can keep making such particles and putting electrons around them, the patterns of the periodic table would continue to hold.

But here’s the catch: We can’t actually do that with nuclei like oganesson (the normal kind made of protons and neutrons, I mean). It doesn’t last long enough to put electrons around it, so it doesn’t have any chemical properties, and has no place on the periodic table.

By that argument, any concept of infinity is invalid. Surely here it’s just shorthand for the question of whether practical considerations are the only constraint, or whether fundamental physical principles prohibit elements above a certain size.

In any case, I made some Googleplex-factorial last week. It tasted like chicken.

I made some, too. Now I’m stuck on (Googleplex-factorial +1). :frowning:

The names won’t be official for five months – which means there’s still time to submit your petition signatures for Lemmium!

While true, one can’t quite make the further claim that all of chemistry is about electrons. The differences are subtle, but deuterium does have different chemical behavior than hydrogen, despite having the same nuclear charge. While they behave the same electronically, their different masses makes a difference in complicated reactions (particularly biological ones).

Iv’e just realized that we’re both blithely reproducing Trinopus’ typo…

Googleplex vs googolplex.

True… and yet, we still regard H-1 and H-2 as both being, fundamentally, hydrogen. And for any given nuclear charge, the chemical differences between normal hydrogen and deuterium are greater than the difference between a normal nuclear mass of any other element and a nuclear mass a million times greater.

Ice made of H[sup]2[/sup] sinks in liquid water …