beta decay

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frochocinco

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i realize there have been questions on this in the past but none of the replies seem to answer the true essence of the question, and that is the part i am confused with.

beta decay is the splitting of a neutron into a proton and either an electron or positron. thus, there should be no debate as to what happens to the mass and atomic number. mass number stays the same and atomic number increases by one

HOWEVER, the issue lies in the identify of the element depending upon whether an electron or position is ejected. my questions are...

if an electron is ejected, why wouldnt the new atom be an ion? you are increasing the number of protons but keeping the number of electrons the same

Secondly, if a positron is emitted, what is the consequence? i'm a little unclear and would appreciate some clarification.

thanks

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i realize there have been questions on this in the past but none of the replies seem to answer the true essence of the question, and that is the part i am confused with.

beta decay is the splitting of a neutron into a proton and either an electron or positron. thus, there should be no debate as to what happens to the mass and atomic number. mass number stays the same and atomic number increases by one

HOWEVER, the issue lies in the identify of the element depending upon whether an electron or position is ejected. my questions are...

if an electron is ejected, why wouldnt the new atom be an ion? you are increasing the number of protons but keeping the number of electrons the same

Secondly, if a positron is emitted, what is the consequence? i'm a little unclear and would appreciate some clarification.

thanks

When discussing decay, remember that it is the NUCLEUS that we are referring to when we say that it "ejected" a particle.

So, in the case of Beta - decay, the electron is ejected from the nucleus at a high kinetic energy. This does indeed create a momentary cation. However, it is highly reactive and will snatch an electron from anywhere that it can. The charged species will most likely only last for a very brief period of time unless action is taken to retain the cationic nature.

In the case of Beta+ decay, the electron antiparticle is ejected after a proton "steals" its charge. The ejected positron will likely find another nearby atom to associate with.

These are incredibly broad generalizations. To gather a real, fundamental understanding of the entire process, you need to delve into quantum mechanics (up quarks, down quarks). This is way beyond the scope of the MCAT. The only things you need to know for the MCAT, in my opinion, are what happens to the number of protons and the number of neutrons with each type of decay and what type of particle is ejected.
 
Stupid question maybe, but how exactly does a nucleus made up of protons and neutrons lose an electron? I am using TBR and they did not mention anything about that, just that it happens.
 
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Essentially, a neutron is decaying into a proton and in the process an electron and electron antineutrino are ejected - this is shown due to conservation of energy.
 
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