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OmegaX7 · 2004-10-13 20:23:46

U-235 is most suitable for bombardment by slow neutrons 'cause it becomes U-236,providing for a more balanced nucleus. So if the electron shells are arranged something like 2,4,8,16,32,18,8,2 the atomic number only changes, in this case, because of an additional neutron. Is this element in a more harmonic state now, is this why it is useful? and U-238; would the same be true simply because it has an even atomic number after bombardment? "Anddoes U-238 have the same electron numbers in their respective shells?
L8R

Chris · 2004-10-19 22:16:09

I moved this post from Quantum to Nuclear.

All isotopes of Uranium are going to have the same number of electrons and the same classical shell structure.

Upon bombardment with slow neutrons, the U-235 isotope becomes the very short lived U-236. U-236 is not stable, that is why it immediately divides into two smaller nuclei, liberating energy and more neutrons. If these neutron are absorbed by other U-235 nuclei, a nuclear chain reaction occurs, and if there isn't anything to absorb some neutrons and slow the reaction, it is explosive.

The problem with U-235 is that it makes up only 0.7% of all Uranium, so there isn't that much of it. 99.2% of Uranium is U-238, which is not fissible -- meaning you can't make a bomb with it.

But here's the cool thing. You can put an extra neutron in U-238, that extra neutron will decay into a proton and an electron. The electron will fly out as $\beta$ radiation and presto, you now have P-239, a fissible, bomb-makeable isotope of Plutonium. This is the stuff Doc Brown used to fuel his Delorian in Back to the Future.

You can also generate clean, inexpensive energy, but that's not as much fun as building bombs

Note to John Ashcroft: I'm kidding. I don't really think building bombs is fun. Although I theoretically know how to build an atom bomb, I have neither the means nor the time nor the interest.

OmegaX7 · 2004-10-21 00:55:34

Ditto on your closing note. However I "have" been reading some of the material you noted. Oh well, I can't afford to run away anyhow.
I found your closing sentence quite humorus; I laughed out loud. Thank you.
So, in some abstract way, I'm not conceptualizing this correctly. I wonder, - the electrons excert a pull on the nucules like so many weights tethered to a central point. Progressing up through the peridic table from "1" to,--- well I don't know to "how many" electrons. What element has the most electrons?? But like some elaborate harmonic balencer, is there some balance to things. At the speed of light and considering Heisinburg"s theory could all the electrons be on one side of the sphere of the nucleus for an underterminable instant and if so would this "pull things apart"? Could this be the unpredictable cause for the unknown time for the decay of any given particle at any particular moment?
So, whats the neutron sorce?? Would this be the reason we can utilize the byproducts from power plants? And is this a transmutation into a new element on the table? I notice you switched from a "U" to a "P", so you mean that when the electron is caught in the field of the 238 that it become something different, 239. I take it thats the total number of particles to the particle once we add the extra electron. - and that changes it into a new element? Cool.
I too have no intentions whatsoever to make any attempt to, or to assist in any way, the construction of an explosive device. Beside, I'm not very good at the assembly of anything much more complicated than killer keg party. If anthing were to go awry i'd have the whole neighborhood mad at me.
L8R

Chris · 2004-11-05 23:40:28

The U is the symbol for Uranium while the P is for Plutonium. We can bombard U-238 with neutrons to make it turn into a Plutonium. The plutonium is unstable and breaks apart.

How do radioactive elements decay? Google "Quantum Electrodynamics" and you will learn. Richard Feynmann won a Nobel prize for this.

What holds the nucleus together even though there are giant positive charges everywhere? Google "Quantum Chromodynamics" to find this out.

hightower 69 · 2005-07-28 02:07:46

So if you insert 160,000 Japanese under a U-238/U-239, what will happen?

Chris · 2005-07-28 15:23:47

Nothing. U-238 is stable. In fact, there are thousands of tons of the stuff right under your feet.

hightower 69 · 2005-08-07 12:34:50

cool, i was unaware of that. But one thing that does confuse me with regards to your answer. just suppose for a second that you do not have feet does that make U-238 unstable? and if so, can this cause an imbalance in the force.

Another question. U-571 when bombarded with radiation, is it possible to create a parralel dimension reminicent of the one capt kirk faced in star trek V?

Chris · 2005-08-07 18:34:18

Your IP address is 203.184.5.210.

Further idiocy will be deleted.

insomnia · 2005-09-02 17:45:21

If you live in England (not sure how many here do) you might have seen a program a couple of weeks a go, chronicling Einstein and various people that set in motion and proved $E=mc^{2}$ . Anyway, this pretty much explain what happens when you fire neutrons at unstable nuclei. The nuclei splits, releases energy and forms a smaller element (lithium or sodium if I remember correctly). So $E$ (energy) is what is created when $m$ (mass) times $c^{2}$ (speed of light squared) The energy relased when they split U-236 and it released 20,000 electrons (energy). Unfortuantely the woman who had split the atom was Jewish and it was around the beginning of the second world war and she was working in Germany, etc. she did not recieve the Nobel Prize. Her male, german friend did. She finally got recognition for her work in the 1960's but she was never been awarded the Nobel Prize.