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What makes you think that it should decay precisely into an electron and a positron, rather than some other option?

Anyway, in any such particle conversion, certain quantities must be conserved. Some of these conservation laws are strict (no exceptions are known to exist), some not (now and then there is an exception). For the proposed reaction, you should consider the following conservation laws:

  • Conservation of mass/energy - the electron and the positron have much less mass than the neutron. This would not pose a significant problem, since they could move away from each other at a high speed - the missing mass/energy would be present in the form of kinetic energy. This indeed happens in some particle reactions.
  • Conservation of momentu - no problem here, either.
  • Conservation of electric charge - no problem here.
  • Conservation of baryon number - this would NOT be conserved in your proposed reaction. Please note that this is not a strict conservation law; there are known violations. However, violating the baryon number in a particle conversion is quite uncommon. In this case, the neutron has a baryon number of +1, the proton (one of the decay products of the actual decay) also has a baryon number of +1, while electron + positron would have a baryon number of 0.
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Q: Why a free neutron does not decay into electron and positron?
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Are beta particles are electrons detached from the nucleus?

During nuclear decay when a beta- particle (a high energy electron coming from the decay event) leaves the nucleus, the action is the result of the transformation of a neutron into a proton and an electron (the beta- particle). Got links if you want them. They are to related articles posted by our friends at Wikipedia, where knowledge is free. Note: there is a bit more to beta decay than was mentioned here, but enough was presented to answer the question. Certainly it is hoped that the links will extend knowledge about as far as the average reader may wish to go.


Can neutrons be divided into protons and electrons?

Yes. We can (and do) smash protons. We can slam them into each other or we can slam protons into antiprotons. Big accelerators do this kind of work. The protons will break up, but the things that we get vary as the type of collisions (and the energies) involved in the smashing project. A proton is composed of two up quarks and a down quark, and a neutron is composed of two down quarks and an up quark. The neutron is unstable outside of a nucleus. It has a half-life of a bit under 886 seconds. That's about 14.8 minutes, roughly. When a free neutron decays, it decays into a proton, an electron and an electron antineutrino.


How do alpha particles beta particles and gamma rays originate in the nucleus of the atom?

A beta particle is created when a neutron inside an unstable nucleus changes into a proton (or vice versa), losing energy and mass in the form of an electron (or positron), which is the beta particle.


What is the difference between free electron theory and nearly free electron theory?

free electron model not take into account the potential neither the electron interaction. nearly free electron take into account the potential.J.C. Aguiar


What does 'neutron' mean?

A neutron is a part of the atom that has a Neutral charge so to say. The atom is composed of an electron, proton, and neutron. Electrons have the negative charge, Protons have a positive, and neutron has no charge. Remember it as in "Neutron is neutral" or "neutron is no". A free neutron (outside of an atom that is) has a half-life of less than 15 minutes.

Related questions

What are the two easily detectable products of the decay of a free neutron?

A free neutron decays into a proton, an electron and an electron neutrino (with a mean lifetime of about 15 minutes). Of these, the proton and electron are readily detectable. Neutrino detection is extraordinarily difficult.


When a neutron decays what does it form?

Outside the nucleus, free neutrons are unstable and have a mean lifetime of 885.7±0.8 s (about 15 minutes), decaying by emission of a negative electron and antineutrino to become a proton: : n0 → p+ + e− + νe


Does a free neutron decay into a hydrogen atom?

A free neutron actually decays into a proton, and an electron and an antineutrino are ejected in the process. This is beta minus decay, and a free neutron is unstable and will decay by this mechanism. While it is true that a proton and an electron make up a hydrogen-1 atom, the decay of the neutron is slightly different. The reason is that the electron leaves the decay event with a high kinetic energy, and it cannot be "held" by the proton (to create the hydrogen atom). Certainly the proton will "pick up" an electron from somewhere after is slows down a bit following its creation, as it, too, has some kinetic energy. The proton will have to release that kinetic energy through scattering, just like the electron that left the event. Links can be found below to related questions with descriptive answers.


Where do the electrons come from in proton proton chain reaction if hydrogen has only a proton in its atom?

when the 2 Hydrogen nuclei fuse, one of the protons is changed to a neutron via beta + decay, this produces an atom of Deuterium, a positron (beta + particle) and a neutrino. This positron will only travel a short distance before contacting an electron and annihilating each other to convert their masses and kinetic energies into the energy of the photons. The electron is most probably a free electron, as the high temperatures involved in Nuclear fusion would have provided enough energy to ionise electrons from their parent atom.


What is the location of the neutron?

a neutron's location in an atom is in the core, or nucleus, of that atom.Where_is_the_neutrons_location_in_the_atom


Are beta particles are electrons detached from the nucleus?

During nuclear decay when a beta- particle (a high energy electron coming from the decay event) leaves the nucleus, the action is the result of the transformation of a neutron into a proton and an electron (the beta- particle). Got links if you want them. They are to related articles posted by our friends at Wikipedia, where knowledge is free. Note: there is a bit more to beta decay than was mentioned here, but enough was presented to answer the question. Certainly it is hoped that the links will extend knowledge about as far as the average reader may wish to go.


Do protons and neutrons have nearly the same mass?

No, the proton and neutron don't have the same mass. A neutron is about 1.00138 times as heavy as a proton. The neutron is just a bit bigger, as you can see, and when a free neutron decays, it releases a proton and an electron. It might be said that a proton plus an electron equals a neutron, but you might not be able to get a physicist to say that. Links can be found below for more information.


Can neutrons be divided into protons and electrons?

Yes. We can (and do) smash protons. We can slam them into each other or we can slam protons into antiprotons. Big accelerators do this kind of work. The protons will break up, but the things that we get vary as the type of collisions (and the energies) involved in the smashing project. A proton is composed of two up quarks and a down quark, and a neutron is composed of two down quarks and an up quark. The neutron is unstable outside of a nucleus. It has a half-life of a bit under 886 seconds. That's about 14.8 minutes, roughly. When a free neutron decays, it decays into a proton, an electron and an electron antineutrino.


What composes a neutron?

A neutron is made of 3 quarks, namely an up quark and two down quarks. It is this composition of quarks that cause it to have zero charge. (An up quark has a charge of 2/3 and down quarks have a charge of -1/3 - thus 2/3 + (-1/3 *2) = 0) A free neutron (that is one that is not bound in a nucleus) will become a proton, an electron and an electron-neutrino. This happens through the weak force (it acts on a down quark, turning into an up). This does not mean a neutron contains an electron. It does not. Yes, an electron appears when a neutron decays, but that electron does not exist in the neutron as an electron, but it does not.


Why conversion of a photon to an electron positron pair is not possible in free space?

Because energy mass conservation will not be satisfied in free space, so that this process needs some material by which this conversion will be proceed.


Where did the heavy elements in planetary objects originate?

The heaviest elements come mainly from supernovae. Iron is the heaviest element that can be produced by fusion. Heavier elements are produced by neutron capture. An individual free-floating neutron collides with a nucleus and merges with it. That doesn't produce a higher element on the periodic table, because the atomic number depends on the number of protons. However, nuclei with too many neutrons are unstable, and will eventually "decay". A neutron will decay into a proton and an electron. Free neutrons don't exist in great numbers in normal stars, so neutron capture doesn't happen significantly in them. Elements from carbon to iron can be formed by fusion in large stars.


Which two particles in an atom about the same mass?

Proton and NeutronOK, in very very round figures, but the neutron actually is more massive.In the first approximation, the neutron's mass about as much as a proton plus one electron or (P)938.235 MeV + (e)0.51098 MeV = 938.74598 MeV.In the second approximation, the energy of the neutrino, photon, and electron velocities ejected in free neutron beta decay would be added, but I can't find that in my references right now so I'll skip the math.There are probably also third approximation terms to account for, if not more.As measured, the neutron's mass is 939.529 MeV.