do we know more sure that we have made all of the elements that we can possibly make

[land_of_ice]

On the table of elements chart it's known that many of the elements are man made? or at least a few of them?
Curious, do we know more sure that we have made all of the elements that we can possibly make? Is that all the combinations of elements that can possibly exist?

Is the theory valid that there is an unlimited number of elements that can be made ?

[Borek]

No doubt we have not yet made all possible elements, but most likely there is a limit to the nucleus size (large nuclei tend to decay much faster) and we are getting closer.

http://en.wikipedia.org/wiki/Transuranium_element

[alxm]

On the table of elements chart it's known that many of the elements are man made? or at least a few of them?

Every one above Uranium (#92).

Is the theory valid that there is an unlimited number of elements that can be made ?

Nope. As Borek points out, they become increasingly unstable with larger nuclei. Although nuclear physicists have predicted there may be 'islands' of relative stability a bit higher up, it's in no way unlimited.

Chemically there's a fairly definite limit, in that we know from theory that elements above #137 (yes, that number (http://en.wikipedia.org/wiki/Fine_structure_constant)) don't have stable electron configurations. I don't think we know exactly what would happen, but I think it's a fair assumption that it wouldn't have stable chemistry.
(Although it occurred to me the limit might come even earlier, depending on how unstable the elements become. If the lifetime of an element is shorter than the average time of inter-molecular collisions (picoseconds), it'd come and go before chemistry had a chance to 'notice')


But hey, who needs elements? :) All of biology exists only using less than 30 elements - and most of them only in trace amounts. The heaviest element used in biology, BTW, is tungsten, utilized by the strange heat-loving bacteria pyrococcus furiosus - who lives near underwater volcanoes and not only survives but thrives in boiling-hot water!

[Borek]

But hey, who needs elements? :) All of biology exists only using less than 30 elements - and most of them only in trace amounts. The heaviest element used in biology, BTW, is tungsten, utilized by the strange heat-loving bacteria pyrococcus furiosus - who lives near underwater volcanoes and not only survives but thrives in boiling-hot water!

Nothing surprising, with melting point at 3422 °C and boiling point at 5555 °C tungsten seems to be the metal of choice for anyone trying to get near volcano :tongue2:

--
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www.ph-meter.info (http://www.ph-meter.info) - ph meter (http://www.ph-meter.info), ph electrode (http://www.ph-meter.info/pH-electrode)

[espen180]

An isotopes 310Ubh and 322Ubh of element #126, unbihexium, has been predicted to be relatively stable. It lies in the g-block in the periodic table, in which there are no elements as of yet.

[StarkRG]

As we get to larger and larger nuclei the periodic properties break down due to relativistic effects. I assume that at some point a nucleus would be so dense as to collapse into a tiny black hole (which would likely evaporate quickly). So that's probably an upper limit. Though, since gravity is the weakest force, perhaps the forces causing the nucleus NOT to collapse would always be strong enough to counteract gravity. (though, that just means that the nucleus doesn't collapse, everything around it still would be gravitationally attracted to it and it would still be in the center of a black hole.

For all we know the center of black holes are giant nuclei of hundreds or thousands of protons (though most likely significantly more neutrons due to electron-proton reactions). On the other hand maybe they're a soupy mess of stuff we wouldn't classify as either matter OR energy.