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Chemical Element 110 To Be Named
An anonymous reader writes "According to Nature Magazine, chemists will vote in Ottawa, Canada this week, and are expected to approve the chemical element 110's informal moniker, 'darmstadtium', and give it the chemical symbol Ds. The title honors the Laboratory for Heavy Ion Research (called GSI) in Darmstadt, Germany, where the substance was first made. It seems that 'disputes over claimed sightings of new elements have [previously] led to acrimonious and nationalistic battles over naming', but not in this case."
Darm, if I'm not mistaken, means 'intestine'. Stadt means city. So this element is Intestine-city-um.
Natural vs. Not-naturally occuring.
It's not quite correct, but basically, they're saying that these other things don't exist unless we try really hard to make them exist in a laboratory.
For instance, gold, mercury, hydrogen: these are all examples of elements that exist in nature (as well as Lithium, Helium, etc, down the line).
Yes, they've existed in very small quantities (sometimes not at all, there have been disputes over this), and under very controlled conditions.
No, of course it's not inconcievable. But remember, elements are created by making a stable (or not so stable) configuration of protons in a little ball. This leaves one to question what is natural: are nuclear explosions and the weapons of the future a "natural" setting?
It's already on the webelements.com page, with some interesting info on the chemical makeup.
Chemical element 110, which was discovered in 1994, will finally get a name tomorrow.
A committee will vote at this weekend's General Assembly of the International Union of Pure and Applied Chemistry (IUPAC) in Ottawa, Canada. It is expected to approve the element's informal moniker, 'darmstadtium', and give it the chemical symbol Ds. The title honours the Laboratory for Heavy Ion Research (called GSI) in Darmstadt, Germany, where the substance was first made.
The natural elements run out at number 92, uranium. Several more have been made artificially since 1939, when researchers at the University of California at Berkeley bombarded uranium with a beam of neutrons to create element 93, which they called neptunium.
Firing subatomic particles at heavy atoms became the preferred method of making new elements. The basic aim is to add more protons to the atomic nuclei - an element is defined by the number of protons its atoms contain. Some new elements were also detected in the fallout from nuclear bomb tests in the 1950s.
Element-making soon became a race. In the 1960s and 1970s the two main players were a Soviet group at the Joint Institute for Nuclear Research in Dubna and a team spanning the University of California and the Lawrence Berkeley National Laboratory. The discoverers of a new element generally win the right to name it, although the new name still has to receive IUPAC approval.
The natural elements run out around
number 92
But disputes over claimed sightings of new elements have led to acrimonious and nationalistic battles over naming. These elements decay quickly, and are often made only a few atoms at a time - so it can be hard to gather convincing evidence.
In 1987 IUPAC was forced to assess priority claims over all the new elements from 104 to 107. Then in 1993 a new controversy erupted when the Berkeley team wanted to name element 106 after nuclear-chemistry pioneer Glenn Seaborg. IUPAC insisted at first that 'seaborgium' broke the rules, because Seaborg was still alive at that time. It relented only after the American Chemical Society threatened rebellion.
No one disputes GSI's claim to element 110. There was, however, some relief when the German results, produced by fusing lead and nickel nuclei, were confirmed last June at Berkeley using the same process1. Element-hunters have been more cautious since a Berkeley team was forced to retract unreproducible data published in support of a reported 1999 creation of element 118.
1) What does this mean exactly?
It means that the first 92 elements can be found naturally occurring, but that after 92 (the trans-uranic elements) have to be produced in a laboratory or under artifical conditions if you want useful amounts.
2) Is it not possible for us to discover other natural elements?
If by discover, you mean create then yes. Since an element is definied by the number of (integer >0) protons, any new elements created must have an atomic number >92.
3) Is it inconceivable that our "new" elements could also be produced under similar conditions in nature?
Not inconceivable. It has been verified that minutes amounts of trans-uranic elements have been found in nature. But given that these lements have a very short life time (before they decay into other elements), you'd have to be around immediately after their formation to detect them in nature. Since their creation requires high amounts of energy, super nova, intense gamma radiation near black holes, etc, are the sort of environments where you might find naturally ocurring trans-uranic elements (remembering too that you basically need to smash into heavy elements to get the trans-uranic ones, the very heavy ones need to be present to). Such environments are are rare and not conducive to observation. Given that the elements in the universe are hydrogen, helium and minor traces short-lived trans-uranic are not going to be found in nature in any partical sense.
4) Have all of these new elements only existed in very small quantities for short periods of time, under controlled conditions?
Yes. There are some theories that there would be an island of stability around element 120+. Scientists are working to create a stable trans-uranic element, and I for one welcome our trans-uranic overlords and would like to remind them that being primarily made of stable isotopes I can be useful in rounding up other carbon based elemental life forms to slave in their radioactive piles.
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The elements above 92 that have been "discovered" in that they could be predicted, but had never been shown to be possible to create before. It is feasible that the high numbered elements could be created naturally, for example in a supernova, however the real problem is that atoms of that size are fundamentally unstable, so have very short half-lives and therefore collapse into smaller atoms very quickly.
It also depends on the isotope of the element, that is changes the ratio of neutrons to protons (the proton count being the atomic number). For example, the half-life of meitnerium (element 109) is most stable as meitnerium-268, ie 109 protons, 159 neutrons, has a half life of 0.07 seconds. So any amount of it produced will not last long. These results are only theoretical, the isotope produced was meitnerium-266, which has a half-life of 3.8 milliseconds.
So yes, they could occur naturally, but not for long enough for anyone to notice.
It's early, that may not have made sense...
Just one more answer I'd like to add to your questions (because so many have been submitted). The natural elements stop occuring after atomic number 92, yes. But it's also worth point out that for all intents and purposes, technetium (element #43) does not exist in nature either.
After decades of searching, extremely small quantites were obtained from pitchblend, but that's negligible.
Long story short (long answer being availabe from google cache here) is that pairing energy makes the atom extremely unstable and causes it to break -a(C)Y quickly.
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Ether was added to the list after Earth, Wind, Water and Fire. No joke - this is old Greek stuff. Someone said ether had circular properties, explaining the moon and cycles in nature...
Surely in vain the net is spread in the sight of any bird -- Proverbs 1:17
The Wooden Periodic Table
:-)
Perhaps some of you knew this one already, but it's one of the most useful ones I've found so far and I really like those huge and high quality pictures they have for most elements that you can take meaningful pictures of.
Beware: In C++, your friends can see your privates!
I remember a little more: nuclei are made of protons (positively charged) and neutrons (no charge), usually in roughly equal numbers (except Hydrogen, which is usually just a proton). The protons repel each other. The nucleus is held together by a very powerful, but very short range nuclear force between both protons and neutrons. As the nucleus gets bigger, the electric repulsion starts to overcome the nuclear force, and the nucleus becomes more and more likely to decay. But I don't remember why you can't just have a pile of neutrons...
Actually #92, Uranium, is unstable, but U238 has a half-life of 4.4 billion years, which is why it's not that hard to find (about half of it has decayed since the creation of the earth). I think all elements above 83 (Bismuth) are unstable. The short-lived ones are found in nature as the result of decay of Uranium or the other longer-lived ones. See this table of isotopes.
Elements are distinguished from one another by the number of protons in their nuclei. Hydrogen has 1, helium 2 and so on. The heaviest naturally occuring element found on Earth is number 92 - uranium.
The limiting factor on elements heavier than 92 is that they are unstable. In fact all of the heavier elements are unstable - they are radioactive, parts of their nuclei keep falling off - they turn into new, lighter elements. So uranium decays step by step, down the periodic table eventually forming lead.
The reason for nuclear decay is a concept known as binding energy - the energy needed to hold a nucleus together. Very simply, the nucleus consists of postively charged protons - each repelling the other. If this repulsion was not counteracted the nucleus would disintegrate. However, the nucleus also contains neutrons - which act very much like glue - sticking protons together. If you measure the binding energy of all the elements you will notice that it rises rapidly from hydrogen, peaking around iron (element 26) and then gradually diminishing towards uranium.
By the time you reach uranium, the binding energy is barely able to hold the nucleus together, beyond uranium, the nuclei of the elements become extremely unstable - they decay - rapidly.
2) Is it not possible for us to discover other natural elements?
Below 92? No. Each element must have at least one proton (in which case it is called hydrogen), we have found each and every element between 1 and 92. You can't have half a proton, so there are just 92 elements in Nature (see proviso below). Some models of atomic nuclei suggest that there are elements heavier than 92 which are comparatively stable - they would be radioactive and decay, but might have considerable half-lives. The theoretical 'island of stability' lies out between elements 118 and 130 (?) - but as yet remains undiscovered.
3) Is it inconceivable that our "new" elements could also be produced under similar conditions in nature?
Yes, supernovae are capable of building up super-heavy elements. However, the short half-lives of the elements mean that they have long since decayed in the rocks around us. The synthetic elements neptunium (93) and plutonium (94) are also generated in minute quantities in naturally occuring uranium.
4) Have all of these new elements only existed in very small quantities for short periods of time, under controlled conditions?
Pretty much, although some of the synthetic elements were first discovered in the residue of nuclear weapons tests.
Hope that helps,
Mike.
Actually everything past bismuth 209 is unstable. 92 is merely the last element to have any isotopes that are stable on a geological timescale (U238 half-life around 4.5 * 10^9 years).
As for why, simply put their nuclei are very loosely held together. Neutrons hold nuclei together with a force known as binding energy (think of it as atomic glue).
For very light elements, (up to around calcium (element 20) stability is achieved by more or less associating one neutron with every proton. However, for heavier elements, an excess of neutrons is needed to hold the nucleus together - the excess growing as elements get heavier.
Simply put (and I hope any physicists will forgive me for this - they have equations and everything!) The electrostatic repulsion between the protons in the nucleus operates over a larger distance than the stronger, binding force of the neutrons. As the nucleus grows, the protons in the nucleus experience a weakening binding force. Beyond a certain point (Bismuth 209) this binding force is insufficient to hold the nucleus together forever - the nucleus will decay.
Best wishes,
Mike.
Yes, and already one such relatively stable element exists-- a single atom of element 114 with 114 protons and 175 neutrons was created that lasted for 30 (!) seconds. This might not be much, but is MUCH greater than lasting for one thousanth of a second like many other elements (z > 100) have.
Theoretically, an atom of element 114 with 114 protons and 183 neutrons is supposed to be perfectly stable (or have a uber-long half life).. 114 and 183 are so called magic numbers where stablity occurs.