[lokifenrir96]

Hi, can someone explain clearly the two different types of beta decay?

I read up and it says Beta- decay involves a neutron being converted into a proton, emitting an electron and antineutrino. Why isn't the product species with an additional proton positive in charge?

Beta+ decay involves a proton decaying into a neutron and emitting a positron and antineutrino. So why doesn't it lose a positive charge? o.0

Thanks!

[Borek]

Where have you found that the charge doesn't change? Wikipedia example shows clearly it does:

[tex]^{137}_{\phantom{0}55}\mathrm{Cs} \rightarrow {}^{137}_{\phantom{0}56}\mathrm{Ba} + e^- + \bar{\nu}_e[/tex]



[tex]^{22}_{11}\mathrm{Na} \rightarrow {}^{22}_{10}\mathrm{Ne} + e^+ + \nu_e[/tex]

[lokifenrir96]

Huh the Ba atom doesn't have a positive charge on it even though the electron was emitted away

[Borek]

Ah, so you are missing the most important part - in nuclear reactions we don't care about electrons, they will find their way to the atom sooner or later. What is important is what happens to the nucleus. [itex]^{137}_{\phantom{0}56}\mathrm{Ba}[/itex] is not an atom - it is the nucleus with a +56 positive charge.

[lokifenrir96]

Okay... I can understand if it's nuclear reactions...

But what if it's in the case of radioactive decay of C-14 to N-14? So are you saying that the electron emitted away will still 'find its way back' to the positive nitrogen ion?

[Borek]

But what if it's in the case of radioactive decay of C-14 to N-14? So are you saying that the electron emitted away will still 'find its way back' to the positive nitrogen ion?

Yes and no - some electron will find its way, it doesn't have to be the same one.

Note that energies involved in nuclear reactions are orders of magnitude larger than the energies we are dealing with in chemistry. Fusion occurs in hot plasma, where everything is ionized and chemistry as we know it doesn't make much sense. Fission may occur at low temperatures, but kinetic energy of the produced nuclei is such that they "jump" far from the place they were produced, colliding with everything on their way, losing electrons and ionizing atoms during these collisions. There is a short period of a complete disorder before all electrons find their way to some unoccupied orbital.

[Arkcon]

Radiation, either alpha particles or beta particles are sometimes called "ionizing radiation" and it wasn't just a cute name.  Pierre Curie saw he could measure radiation given off from a substance by measuring the electrical conductivity between two separated plates.  The radioactive particles, traveling through the air, would ionize the air, making it carry more charge.  It'll do the same thing to living tissue ... and suddenly charged biomolecule, especially DNA, don't work the way they should.  This is what makes alpha and beta particles dangerous to living things.