[Brunno]

Hi there everybody,

I was studying radioactivity searching a lot on internet but i didn't get much about what is implicit on the study.I read about half-life,radiations alpha,B and Y but still don't understand what is it exactly.Let me formulate better the question,but first i must tell you guys that my english is not one hundred percent ,ok?
It is known that a radioactive element has a half-life,some it is nothing but less than a second and some are about billions of years.Until this point the question is not yet answerd: a element has a certain amount of atomic mass,which means that a element as a uranium,for example,can not just free alpha radiation every second or minute once it has less than tree hundred protons plus neutrons.So,what kind of radiation is libareted from atoms as these and if there's a equation that rules each moment a radioactive atom will liberate an alpha radiation?

[Borek]

I think what you are missing is that it is not a single atom that we are talking about, but a huge amount of atoms.

Say you have several grams sample of uranium. Uranium is radioactive, so some of the atoms will decay. Once they do, they are no longer uranium - they became something else, so your sample contains mixture of elements. But, at least initially, it is mostly uranium. After half life half of the original atoms will be there, combined with decay products.

[Brunno]

Yes, this makes much logical sense to understand,'coz than you have a sample that there's a large number of atoms and so there's space to each one decay on its time and all the three radiations alpha,b an Y can happen.It's interesting to see that if this happens just like this it means that each atom has a big time interval among them when they were formed.But that explain too why we have a not much large amount of such elements.I guess that's more and less the way to think...isn't it?