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Bismuth No Longer the Heaviest Stable Element
forii writes "Bismuth-209 was commonly thought to be the heaviest stable element. But now Physicists have discovered that Bi-209 actually is unstable and decays with a halflife of 2*10^19 years. This means that the average 8oz (237ml) bottle of Pepto-Bismol contains one decay event every 36 hours or so."
[shock-rag wire service] Scientists discover that bismuth, a major component of Pepto-Bismol , is RADIOACTIVE and decays into the TOXIC POISON thallium.
While the decay rate is the slowest observed to date and, in fact, sets a record, it is noted that NO MINIMUM SAFE EXPOSURE LEVEL has been established for radiation exposure, and there is NO CURE for thallium posioning.
You could've hired me.
Bismuth-209 was commonly thought to be the heaviest stable element.
Actually, most of the scientists believed it was stable, however not everyone. (Some of them were considered "crackpots" by the rest of the community, but the point remains valid, even if somewhat less so.) Try a Google search.
Karma: Positive (probably because of superiour intellect)
That's a really long time. I mean, really long. The universe is considered to be 15 to 20 billion years by most who decide to actually guess. That means that, if the universe is 20 billion years old... and 1 g of Bi-209 was produced at the beginning of the universe, it would take another 1.999999998*10^19 years before half of the Bi-209 was left. I wonder if our universe will even reach that age, if the big bang 'cycle' theory holds to be true.
OMG, you're right! At one event per 36 hours, it's practically a fucking Omega Particle!
Someone call Starfleet! *KILL IT! *KILL IT!
(*read: start a new government agency dedicated to the analysis and monitoring of this tool-of-terrorists; fund a few dozen fact-finding junkets, c/o the taxpayer; draft an array of pointless laws regarding Bi research, don't forget to call the religious end-of-world nutters for their valuable insight; end up hiring a PR agency to divert attention away from the fact that you've accomplished bugger all, were wrong all along, and now have a $30mil mansion on the harbour).
Opportunity knocks. Karma hunts you down.
Does 'stable' mean that decay hasn't been observed, or that it NEVER occurs?
How does quantum mechanics apply to decay?
Does an atom decay when a certain set of positions occur within it, and if so why can't the frequency that this would occur at be calculated?
A pizza of radius z and thickness a has a volume of pi z z a
Incidentally, all elements have unstable isotopes. Bismuth's are pretty rare, but they do exist!
Bismuth obsessive will rejoice in the web site of the Bismuth Producers Association.
I prefer Tums, myself.
Bismuth-209 is the most common isotope of bismuth (with its mean atomic mass being 208.98038), so it would be acceptable to say ' Bismuth No Longer the Heaviest Stable Element', according to webelements and The Jefferson Lab.
...Pepto Bismal will be in short supply. And just when people really need it!
If you look at the periodic table, the answer is obviously the next smaller element, lead, which is what most of the heavier elements eventually decay to.
You are in a maze of twisty little passages, all alike.
GAITHERSBURG, MD
22 May 2003
Today, the National Institute for Standards and Technology, the civilian agency of the US Government responsible for researching and making available data concerning the physical properties of substances including chemical elements, annouces the discontinued use of francium as the name of the 87th chemical element.
"It's just not appropriate to continue to refer to an element by the name of a nation whose inaction is tantamount to condoning terrorism," said Dr. Hratch G. Semerjian, director of the Chemical Science and Technology Laboratory. "We decided that it would be better to refer to the 87th element as Freedomium in honor of those who died to secure the liberty of our country.
Asked if the agency would once again return to calling the 87th element francium, Semerjian said that the element would not return to its former name. "We are prepared to take whatever action is necessary to liberate any element whose nomenclature is derived from a repressive regime."
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> At one event per 36 hours
Remember, that's just an average. Your experience may be different. It could decay all at once just after you swallow. You can't be too careful.
Not only that, he never said "it's" when he meant "its".
My favorite element, by the way, is Osmium. It sublimates dreadfully toxic fumes from a solid state at room temperature, and nobody knows exactly what its specific gravity is, nor whether it or Iridium is the heaviest element.
How about "Bismuth not stable; Lead now heaviest stable element". (Polonium has no stable isotopes).
Ok, not only did you catch me in a dyslexism, you came up with a better headline. For that you will suffer!
This could prove to be the most important use of this technique, as most proposed Grand Unified Theories have interactions that can turn quarks into leptons, so that a proton would be expected to eventually decay into a positron and a meson. Unfortunately, this process has never been observed (well, only somewhat unfortunately, as high proton stability is definitely a Good Thing in most ways), and experiment and theory have thus set a lower bound on the lifetime of a proton of roughly 10^33 years, about 23 orders of magnitude greater than the estimated current age of the universe.
As you can see, compared to the suggested lifetime of a proton, even Bi-209 seems unstable. The expected extreme rarity of a proton decay event, however, is somewhat balanced by the overwhelming abundance of protons in the universe.The "lifetime" for an individual proton is more like a life expectancy, an average figure- given a suitably large collection of protons, odds are good that at least one would decay in a reasonable timeframe. If you carefully watch 10^33 protons for a year, for example, and reality agrees with theory (big if), then it is likely (certainly not guaranteed though) you will see at least one decay event. Now, 10^33 may sound like a tremendous amount, but remember that each proton has a mass of only 1.67*10^-27 kilograms, so that 10^33 protons would have a mass of about 1,600 metric tons- a lot, but not outrageous.
The real problem lies in that "carefully watching" part. So many other forms of radiation are much more prevalent, and so might mask the signature of proton decay. Cosmic rays, naturally occuring radioisotopes in places you'd never think to look, solar neutrinos, that sort of thing. Ah, why yes, this is one of those experiments they do in a salt mine and uses a gigantic tank of ultrapure water (your proton source). However, as of yet, no one has found concrete evidence for proton decay from one of these experiments. Go here for a excellent site about a proton decay detector that ran in the 80s, and here for one currently in use.
Perhaps this process will detect this very rare event, lending profound support to one of the many supersymmetric models out there. Unfortunately, if it does not detect proton decay, it will be much more difficult to say just what the result means, it being difficult to prove a negative and all.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
Since there are likely to be a number of people teading this that have good command of the topic, let me ask a question on isotopes. All through school I was taught that different isotopes of an element have the same chemical property. That information is still found in most articles on the subject. Yet I recently found a reference that Heavy Water was poisonous. Since there is no radiation danger, how can heavy water be poisonous if isotopes are chemically identical? What is going on here? And what are the indications of heavy water poisoning?
I'm an American. I love this country and the freedoms that we used to have.
Heavy water poisoning of animals is caused by the D2O (heavy water) inhibiting cell division (mitosis). Bacteria growth rates are reduced, leading to problems in the GI tract, and bone marrow activity is reduced. So GI infections and enemia are symptoms. You would need to approach about from about a quarter to about a third of your body weight in D2O to achieve toxic levels. It would cost in the vicinity of $10,000 dollars and you would weight several pounds more when you died.
---- ---- --- -- --- ------ Keep Cool But Do Not Freeze
looks like the pepto-bismol people already knew about this
http://www.pepto-bismol.com/faqs.htm#8
How do I read the expiration Date? Can I use Pepto-Bismol® past the expiration date?
Expiration date example:
EXP JL02C0041
EXP = expires
JL = indicates the month (July)
02 = indicates the last digits of the year (2002)
C0041 = indicates plant and production information
If your Pepto-Bismol® has expired, please do not use it. The ingredients may not be stable after the expiration date.
that would be EXP JL20000000000000002003C0041 I suppose, it should be safe to drink for a while yet.
"Taligent is still pure vapor. Maybe they'll be the last who jumps up on Openstep... "
that's just an average... It could decay all at once just after you swallow
:)
True, you're far more likely to have the hydrogen atoms in a glass of water spontaneously fuse after you drank it. If the bismuth decayed all at once it would kill you, but if hydrogen fused all at once it would kill everyone in a 50 mile radius.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
My dad had a copy of Lange's Handbook of Chemistry that was published back in the sixties. I distinctly remember seeing that it listed the half life of Bi-209 as 2x10^23 years. That was only four orders of magnitude too long.
In principle there are no stable nuclei heavier than iron 56. If you have a nucleus with atomic number A and atomic weight X, and you add up the binding energy of that nucleus, and compare it to the sum of the binding energies of an alpha particle and of a daughter nucleus with atomic number A-2 and atomic weight X-4, you will find that alpha decay is at least a little energetically favorable for many nuclei heavier than iron.
If alpha decay is energetically favorable for a nucleus, then that nucleus is not stable. Alpha decay is a barrier tunneling process. If there's a potential energy drop on the other side of the barrier, the barrier will get tunneled through by an enterprising alpha particle eventually. It's just a matter of how long it will take- which is determined by the barrier width and the magnitude of the potential energy difference. The only reason many elements (iodine, gold, mercury, lead, etc.) are considered stable by human beings is that their decays have never been observed- because they are difficult to observe within human time scales. You might have to set up your experiment and wait for years, maybe centuries, before you see a decay. A bottle of mercury might contain two alpha decays per century. Is mercury stable? Not really, but for all practical purposes it is. It's all in the eye of the beholder.
So it seems someone has caught bismuth in the act. Does this mean lead is now the heaviest stable nucleus? No, absolutely not. Lead has some advantages over bismuth- even numbers of neutrons and protons, etc. Pb-208 will definitely have a longer half life than Bi-209. Determining the half life of Pb 208 is going to be hard. But quantitative differences aside, the only real difference between lead and bismuth is that bismuth got caught!