Qs on nuclear decay (1 Viewer)

[jennisfayer]

pls help...
238 92U →234 90Th + 4 2He 〓a decay

234 90Th →234 91 Pa + 0 -1e 〓b decay

234 91Pa →234 92U + 0 -1e 〓b decay

234 92U →230 90Th + 4 2He 〓a decay

……（until n/p=1:1）


how does the isotope get a new proton from b decay to increase the element number?
what's gamma ray do during decay? does it emit from nucleus?

 

[Dreamerish*~]

238 92U →234 90Th + 4 2He 〓a decay

234 90Th →234 91 Pa + 0 -1e 〓b decay

234 91Pa →234 92U + 0 -1e 〓b decay

234 92U →230 90Th + 4 2He 〓a decay

……（until n/p=1:1）


how does the element get a new proton from b decay to increase the element number?
what's gamma ray do during decay? does it emit from nucleus?

Beta particles (electrons) come from the nucles of the atom, not from the electron cloud. The nucleus contains only protons and neutrons, so to emit an electron, the neutron "decomposes" to give an electron and a proton.

¹₀n → ¹₁p + ⁰_-1e

The atomic number represents the positive charge on the particle, so when a neutron "decomposes" to an electron and a proton and emits the electron, the positive charge is raised by 1 because of the proton that is the other "bit" of the "decomposed" neutron that is still in the nucleus.

Gamma rays belong to electromagnetic radiation. They have no mass, no charge and have extremely short wavelengths and therefore high penetrating power. They are emitted with alpha or beta particles, not on their own.

 

[Haku]

dreamo, u know when u make synthesis radio isotopes u can either do it on cyclotron, nuclear reactor and linear accelerators. cyclotron can only bombard the parent atom with proton while nuclear reactor and accelerator does both proton and neutron. is that right?

also i dun get it why u can;t bombard atoms with helium nuclei.

 

[Captain Gh3y]

*physics*

Cyclotrons use magnetic fields to accelerate particles... neutrons don't really care much for magnetic fields.

As far as I know, nuclear reactors can only bombard the parent with neutrons, because you've only got free neutrons going in a nuclear reactor, basically they are a chain reaction of uranium + neutron --> 2 smaller things + 3 neutrons etc.

I don't know about linear accelerators.

As for helium nuclei not being able to be absorbed by the parent nucleus, I'm 90% sure that's because of the law of conservation of momentum; they just bounce off.

 

[Dreamerish*~]

dreamo, u know when u make synthesis radio isotopes u can either do it on cyclotron, nuclear reactor and linear accelerators. cyclotron can only bombard the parent atom with proton while nuclear reactor and accelerator does both proton and neutron. is that right?

also i dun get it why u can;t bombard atoms with helium nuclei.

Cyclotrons and linear accelerators are used for bombarding with charged particles, and nuclear reactors bombard with neutrons. This is enough for the syllabus, which requires you to know how transuranic and commercial radioisotopes are produced - all you need to say is neutron or charged particle bombardment using a nuclear reactor or positive ion accelerators and chuck in a couple of equations.

I don't see why you can't bomobard target nuclei with helium nuclei. Where does it say you cant?

 

[Haku]

Cyclotrons and linear accelerators are used for bombarding with charged particles, and nuclear reactors bombard with neutrons. This is enough for the syllabus, which requires you to know how transuranic and commercial radioisotopes are produced - all you need to say is neutron or charged particle bombardment using a nuclear reactor or positive ion accelerators and chuck in a couple of equations.

I don't see why you can't bomobard target nuclei with helium nuclei. Where does it say you cant?

whats the difference in the production b/w commercial and transuranic elements?

also many people tell me that u can;t bombard with helium nuclei, dun know y

 

[Captain Gh3y]

We don't use plutonium, neptunium or curium in medicine or industry.

Technetium 99 and Cobalt 60 aren't transuranic. That's the main difference.

When an alpha particle strikes a larger nucleus, it bounces off. (So do neutrons, unless they're going really slow).

 

[Dreamerish*~]

whats the difference in the production b/w commercial and transuranic elements?

also many people tell me that u can;t bombard with helium nuclei, dun know y

Not all commercial radioisotopes are transuranic, and not all transuranic radioisotopes are commercial.

The difference between the production of the two is with transuranic, you bombard target nuclei with neutrons or charged particles to see what you end up with that has an atomic number of >92. With commercial, you know what you want, so you have to be specific on the reaction you use. For example, cobalt-59 is bombarded with a neutron to form cobalt-60.

 

[Haku]

i know that a transuranic substance is one with higher atomic number than 92. and all transuranic elements are made from uranium bombarded with neutron. but what other difference in production does it have with commercial isotopes.

oh and can lower atomic number atoms be bombarded with helium to for radioisotopes?

 

[Haku]

damnit, always 1 step behind u. i was just typing u know........now it seemed i copied what u said!!!

oh can some one post up there notes for that dot point. i still have trouble getting it.

 

[Dreamerish*~]

damnit, always 1 step behind u. i was just typing u know........now it seemed i copied what u said!!!

oh can some one post up there notes for that dot point. i still have trouble getting it.

Edit your posts instead of creating new ones!

 

[Haku]

sorry madam, just that u stalk this forum too much and too quick to grab posts and providing info. its like ur running a monopoly.

anyway this is from timmy, from the site hsc-mirror

5.2.2 describe how transuranic elements are produced
Transuranic (elements with larger mass than uranium) were originally produced by bombarding nuclei with neutrons. As technology developed, transuranic elements were produced by bombarding large nuclei with positive particles of a high velocity such as helium and carbon.
5.2.3 describe how commercial radioisotopes are produced
Commercial radioisotopes are produced by placing fuel elements into the reactor core for about one week. The uranium decays to molybdenum-99. During its time in the technetium-99m generator, the Molybdenum-99 continually decays to technetium-99m. When the generator reaches its final destination, the technetium-99m can be extracted without removing it from the heavily shielded
container. This is achieved by flowing normal saline solution through the alumina.


i remember how transuranic elements are produced, but the method outlined for the commercial isotope i never heard of or understand. is it saying that all commercial isotope is a daughter product of uranium? and that is placed in a reactor and wait for it to decay to a suitable product of use and than extracted at that time?

but the problem i see with that is that uranium got a half life of 200+ years (i think its that long)...

 

[Dreamerish*~]

sorry madam, just that u stalk this forum too much and too quick to grab posts and providing info. its like ur running a monopoly.

anyway this is from timmy, from the site hsc-mirror

5.2.2 describe how transuranic elements are produced
Transuranic (elements with larger mass than uranium) were originally produced by bombarding nuclei with neutrons. As technology developed, transuranic elements were produced by bombarding large nuclei with positive particles of a high velocity such as helium and carbon.
5.2.3 describe how commercial radioisotopes are produced
Commercial radioisotopes are produced by placing fuel elements into the reactor core for about one week. The uranium decays to molybdenum-99. During its time in the technetium-99m generator, the Molybdenum-99 continually decays to technetium-99m. When the generator reaches its final destination, the technetium-99m can be extracted without removing it from the heavily shielded
container. This is achieved by flowing normal saline solution through the alumina.


i remember how transuranic elements are produced, but the method outlined for the commercial isotope i never heard of or understand. is it saying that all commercial isotope is a daughter product of uranium? and that is placed in a reactor and wait for it to decay to a suitable product of use and than extracted at that time?

but the problem i see with that is that uranium got a half life of 200+ years (i think its that long)...

Hey, I'm competing with you for chemistry moderator. Thread-stalking is a must!

The description of commercial radioisotope production isn't, well, a description of commercial radioisotope production. It's only telling you how technetium-99m is made. You just need to know that commercial radioisotopes are generally made from neutron-bombardment of target nuclei. For example, bombarding cobalt-59 with a neutron to produce cobalt-60.

 

[pLuvia]

Sorry for going off the topic but, Dreamerish when did you become Benefactor? just today right? and now your trying for Chemistry Mod

 

[Dreamerish*~]

Sorry for going off the topic but, Dreamerish when did you become Benefactor? just today right? and now your trying for Chemistry Mod

Actually, I applied for moderator last night, and became a benefactor this morning.

 

[pLuvia]

haha congrats You'll become one soon, your a smart one

 

[Haku]

hehe, cool.

did the idea come when i was asking how to become a mod?

anywayz i didn;t get a chance last night, besides u got better qualification ,

are there any openings in phy, eco or eng moderator possitions? and who do u send application to?

 

[pLuvia]

Didn't you already ask this question before to jm1234567890? Anyway to any mod I guess

My fault for bringing this thread out of topic