# Tag Info

13

Iron is a "special" element because of its nuclear binding energy. The very basic idea is that when you fuse two light elements together, you get a heavier element plus energy. You can do this up to iron. Similarly, if you have a heavy element that undergoes fission and splits into two lighter elements, you also release energy. Down to iron. You can see ...

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If by "currently" you mean right this second, then probably -- but we won't know until it works. But if you mean recently, and I'm sure people are working on more, then the answer is yes. If you look at this table, you'll see that the newest entry is 2010 for Ununseptium. So people are interested in creating new elements. As for why, my personal ...

3

Protons are positively charged, and neutrons are neutral, so large nuclei are highly positively charged. A postively charged sphere will energetically prefer to break up into two separate charged droplets which move far apart, this reduces the electrostatic energy, since the electrostatic field does work during this process. This thing, spontaneous fission, ...

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It's not easy. However there are attempts to calculate a phase diagram of an element from first principles. For example, in this paper http://prl.aps.org/abstract/PRL/v95/i18/e185701 the solid-liquid transition of diamond is calculated. The calculation of the free energies is done with ab initio molecular dynamics. This means that the carbon nuclei are ...

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According to this site, we have about 433 working reactors, 65 under construction, 160 planned and 323 proposed which is too many... We're consuming about 67,990 tons per year of U-238 which would probably die out soon within about 75 years. Besides fission products, spent fuel rods contain some plutonium produced by the U-238 in breeder reactors by ...

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In fact, some nuclear theorists do believe that there will be relatively stable heavy elements, as per your point 2. The so-called Island of Stability is predicted to occur because stability is maximized at certain so-called magic numbers which correspond to especially stable isotopes when the number of protons and/or neutrons matches one of the numbers. In ...

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Metallic hydrogen is a metal that's not found on earth (but may be present in Jupiter): http://en.wikipedia.org/wiki/Metallic_hydrogen Wether it does anything but evaporating or burning at ambient temperatures and pressures (or whatever conditions those aliens encountered in this movie), I don't know. Since metals a generally in the lower left corner of ...

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First part: From the formula for the radius, and the fact that magnetic field is the same in both cases, you get: $$B = \frac{m_1 v_1}{q_1 r_1} = \frac{m_2 v_2}{q_2 r_2}$$ Because you don't know the velocities, you want to get them from the potential difference. You also have $$v = \sqrt\frac{2q V}{m}$$ You put that back into the first equation, and ...

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According to the WNA site, at the current usage (68,000 tU/yr), the world's present measured resources of uranium (5.3 Mt at present spot prices and used only in conventional reactors) are enough to last for about 80 years. This represents a conservative estimate as further exploration and higher prices will yield further resources.

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The previous answers also assume we stick with current Uranium reactors. Thorium is about 4x as common as Uranium and also makes a good nuclear fuel. So far there hasn't been much research into Thorium reactors because Uranium is pretty common and reactors use so little of it (a few ton/year) that fuel availability hasn't been a major driver. Thorium has ...

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If you use a PACER nuclear power plant, where you blow up H-bombs in an undeground cavity, and the bombs are 99% fusion (as they should be in a good design) the neutrons emitted by the bombs will more than compensate for the plutonium used up in exploding them. The neutrons will breed more plutonium, and breed unstable elements into stable ones, or convert ...

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Well, meteorite minerals like iridium and all aren't really found on Earth in appreciable quantities. What you're looking for are exotic atoms. These certainly exist, but are too unstable. And, for certain exotic atoms like onia, atomic number isn't even defined. The binding forces cannot be different since the coupling constants are...well... constant ...

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The position of the Lanthanides and Actindes in the periodic table is due to their electronic orbital position. While the group number of an element does correlate with physical and chemical properties, it primarily informs you of the electronic configuration. In the case of elements 90-92, they have electrons in the f-orbital, so sit comfortably in the ...

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