Is the periodic table still getting new additions?

Comments

• SnotFlickerman@lemmy.blahaj.zone ⁨1⁩ ⁨day⁩ ago

  Periodically, yes.

  …I’ll show myself out.

  source
• Bags@piefed.social ⁨1⁩ ⁨day⁩ ago

  The elements at the very end of the periodic table are somewhat tenuous as we know "elements" to be, as there has only ever been very VERY small amounts of this material produced, and the isotopes of those materials that ARE produced split apart almost immediately with insanely small half-lives, so it's not like there's any amount of it just kicking around in a jar somewhere in some lab.

  There's a ton of interesting reading on the theoretical island of stability in superheavy elements
  https://en.wikipedia.org/wiki/Island_of_stability

  I think there are elements theorized up to around atomic number 125 or 127. Currently the highest confirmed, named, and somewhat categorized is 118.

  source

  • TranquilTurbulence@lemmy.zip ⁨1⁩ ⁨day⁩ ago

    See also: chart of nuclides

    It contains the periodic table and all the unstable isotopes of every element. The island of stability would be somewhere in the top right corner, outside the chart.

    When you look at the half-life data, it’s pretty clear that lead is the last fully stable element. Anything past that line (126 neutrons) is more or less unstable, but not necessarily useless. For example, uranium and thorium are pretty far away, but they can still have practical applications.

    Between hydrogen and lead, stable isotopes are abundant, but after lead, finding anything you can reasonably do chemistry with gets a bit scarce. When you go past plutonium 244, you’ll find even less chemistry there.

    source
  • trolololol@lemmy.world ⁨1⁩ ⁨day⁩ ago

    When you say macroscopic time are we talking about seconds or years? Wondering whether we can actually build a circuit or something if we could produce a few mg of it.

    source

    • Bags@piefed.social ⁨1⁩ ⁨day⁩ ago

      It depends on which theorist you talk to. Some say seconds to minutes, others say days to weeks, the nutcases say thousands to millions of years.

      And at the end of the day, the electrical properties of these elements probably aren't that interesting or useful, and almost certainly won't be like, semiconductors or anything fun. Just dumb, heavy, really fucking radioactive wire lol.

      source

      • -> View More Comments
• neidu3@sh.itjust.works ⁨1⁩ ⁨day⁩ ago

  Yes-ish. The elements “exist” in a theoretical state: The higher the atomic number, the more unstable they are, so you won’t find them in nature.

  However, they can be created temporarily in labs, and they exist a short amount of time before they decay into more stable particles. When a previously unibserved element is created, it gets added to the table.

  What makes an element stable or unstable is beyond the scope of this question, but in general, the heavier an element is, the more unstable it is, and we’ve already discovered the lightweight ones. The Island of Stability has been theorized, so once we reach the tech necessary to create elements from there, we might see a large amount of new elements added.

  source
• TabbsTheBat@pawb.social ⁨1⁩ ⁨day⁩ ago

  The last new element was like… 2016? So depends on what counts as new I suppose :3

  source

  • BartyDeCanter@lemmy.sdf.org ⁨1⁩ ⁨day⁩ ago

    To expand on this, there aren’t any gaps left so the only new ones will be increasingly heavyweight and have vanishingly short half-lives, which means that they are increasingly difficult to synthesize and detect. In theory there is an island of stability once we can synthesize sufficiently heavy elements, but it seems pretty far off.

    source

    • Bags@piefed.social ⁨1⁩ ⁨day⁩ ago

      The "island of stability" actually encompasses many of the superheavy elements that we have already produced. The "stability" part comes from "magic numbers" of neutrons in the isotopes that are theorized to have some kind of stabilizing effect on the nuclear shells.

      The difficulty is that we can theorize the number of neutrons we need to stabilize a certain number of protons, but finding atoms with the right number of protons and neutrons to smash together to hopefully create that total number is... difficult. Sometimes those particular isotopes with the proton/neutron quantities required either just plain don't exist, or are themselves a wholly synthetic isotope with its own set of problems like being insanely slow or difficult to produce, having a crazy short half-life, etc.

      source
• Vroomfondel@lemmy.ml ⁨1⁩ ⁨day⁩ ago

  My ELI5 answer: The periodic table is basically “finished”, there are no new additions. Meaning, the structure is is set and almost all elments found, including some (theoretical) higher-number elements that still have to be securely “discovered”. This final discovery nowadays happens only in specialised labs from time to time, because the higher-number elements are extremly unstable, only created artifically and existing for a few nanoseconds or femtoseconds. Some more details you can find on Wikipedia here: en.wikipedia.org/wiki/Actinide

  Additionally, some people discuss different models/structures for organising the elements in general. But that is a different topic.

  source

  • foggy@lemmy.world ⁨1⁩ ⁨day⁩ ago

    Nuh uh I’m working on ununununium.

    source

    • jewbacca117@lemmy.world ⁨1⁩ ⁨day⁩ ago

      You’re excited now, but just you wait until I finish unununununium!

      source
    • Magister@lemmy.world ⁨1⁩ ⁨day⁩ ago

      Now write it in cursive!

      source
  • TrojanRoomCoffeePot@lemmy.world ⁨1⁩ ⁨day⁩ ago

    Bingo, @Madbrad200@sh.itjust.works , see the wikipedia entries which climb as high as 116: en.wikipedia.org/wiki/Moscovium

    If you want to go on a fun rabbithole dive, take a gander at what Bob Lazar has to say about Moscovium (115), and its use in craft by nonhuman entities.

    source
• dhork@lemmy.world ⁨1⁩ ⁨day⁩ ago

  My (flawed and amateur) understanding is that they create new elements by smashing together atoms on particle accelerators to see if their nuclei stick. If you can create an atom with a new number of protons in its nucleus, in a manner which can be repeated, then you have created a new element.

  The last new element that was created with a natural process was found sometime in the 1930s. Many of the artificially generated elements are extremely unstable. Our labs may be the only place in the universe they are made, that aren’t inside stars.

  source