Is a neutron made up of a proton and an electron?

Question

My science teacher says no, but if it isn't, then why is it during beta decay, the neutron turns into a proton and releases an electron?

Answer 1

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the first 2 answers above are correct but don't really answer the question.

what you are asking about is a so-called "weak decay" process, i.e. this process occurs because of the exchange of a W boson.

basically a down quark (in a neutron) converts into an up quark and a W- (which conserves charge of course). this W- is very heavy and is thus very short-lived (see Heisenberg uncertainty). the W- decays into a an electron and an antineutrino.

so the process is n -> p + W- -> p + e- + anti-nu_e.

it is not that the neutron contains a p and a e as constituents, but that the weak force is in play. as the neutron mass exceeds that of the proton, this decay process is energetically allowed.

there are a number of related processes also governed by the weak interaction. these are positron emission and electron capture (as well as bouble-beta decay, but which is a lot rarer)

cheers

Answer 2

The best way to explain this in simple words, is that neutrons, protons and electrons consist of even smaller particles, called quarks. These quarks come in different types and with different electric charges. Different arrangements of various quarks make up the neutrons, protons and electrons.

The neutron consists of two down quarks with charge -1/3 and one up quark with charge +2/3, and the decay of one of the down quarks into a lighter up quark can be achieved by the emission of a W boson. By this means the neutron decays into a proton (which contains one down and two up quarks), an electron, and an antineutrino.

Source(s):

http://en.wikipedia.org/wiki/Neutron

Answer 3

Well, the deal is that you've ignored quarks, and ignored how that decay really works. A beta- decay releases an electron and an antineutrino.

A neutron is made up of quarks. In beta- decay, a down quark converts to an up quark and W- boson is emitted. The W- boson then decays into an electron and an antineutrino.

Source(s):

http://en.wikipedia.org/wiki/Beta_decay

Answer 4

Well, your science teacher is right. A neutron is made of three quarks (two down -1/3 quarks and one up +2/3 quark). Notice the -1/3 + -1/3 + 2/3 = 0 -> This is why a neutron has no electrical charge. A proton is made of the same quarks in different proportions (one -1/3 and two +2/3 quarks). Here -1/3 + 2/3 + 2/3 = 1 so this is where the protons charge comes from.

To go further is beyond the scope of something I could easily write up and is pushing my understanding of quantum mechanics to begin with. There are several websites that will give you the details though... just search for "neutron beta decay".

Answer 5

no idiot .. a atom has a proton neutron and an electron