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Positrons can be produced in atomic nuclei by some kinds of radioactive decay, and they can be observed to be leaving a nuclear reaction called beta plus decay. But the positron leaves the nucleus of an atom as soon as it is created. It does not (cannot) exist in the nucleus of an atom.
Wiki User
∙ 13y ago
Wiki User
∙ 8y agoA positron is one of the beta particles emitted from the nucleus of a radionuclide during beta decay, mediated by the weak force; the other particle being an electron. In beta-plus decay, a proton emits a positron and becomes a neutron. The reason behind it is because of instability in the nucleus; the decay allows the nucleus to achieve a more optimal ratio of neutrons to protons and thus higher stability.
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Why don't positrons annihilate the electrons in the same atom when they're released?
The positron released from an atomic nucleus in positron emission (or beta plus decay) appears with high kinetic energy. It's moving very quickly, and because it is, it has an extremely low probability of actually interacting with that atom's electrons in mutual annihilation. That positron will undergo some scattering events to dump energy, and only then will the probability of it being able to actually "combine" with an electron increase to the point where it will actually do so.
A positron orbiting an antiprotron would make up an atom of?
Anti hydrogen , antimetter.
Where in the atom is the mass of the atom concentrated?
It is the nucleus. Mass of electrons is too small
What is the change in atomic number when an atom emits a positron?
Emitting a positron, turns a proton into a neutron. So the atomic number goes down by 1, while the mass number remains the same.
What is an atom that contains the protons and neutrons?
It is the nucleus. It is the middle of the atom
What is the name of the particle that orbits the nucleus of an atom?
The electron is the sub-atomic particle that orbits the nucleus of an atom of matter. For anti-matter the sub-atomic particle that orbits the nucleus is the anti-electron (positron).
How does positron emission cause nuclear transmutation?
It is in beta plus decay that we see the positron emitted from the nucleus. (An electron is emitted in beta minus decay.) Within the nucleus of an unstable atom, a proton transforms into a neutron, and a positron is ejected from the nucleus (along with a neutrino). As the nucleus now has one more proton than it did before, its atomic number just went up by one; it is another element.
When radioactive phosphorus decay it emits a positron will the resulting nucleus be another isotope of phosphorus?
No, whenever an atom emits a positron its atomic number is decreases by one unit (because a proton is converted into a neutron and a positron) but atomic mass remains the same so phosphorus is converted into silicon atom with same atomic mass.
What is positron capture?
The decay of an unstable atom by absorbing a wandering positron into the nucleus, converting a neutron into a proton. One example is how a radioactive form of iodine, 131I, can use positron capture to become xenon, 131Xe. This is a stable, so the conversion is a big help.
Why do positron emission and electron capture have the same effect on a nucleus?
The reason positron emission and electron capture have the same effect on the nucleus of an atom is because the resulting atom undergoes nuclear transformation, and the new element will have one less proton and one more neutron than the precursor element. Both of these nuclear changes are interesting, so let's look a bit more closely. In positron emission (also called beta plus decay), a proton in the nucleus of an atom "changes" into a neutron and a positron is ejected. This results in one less proton in that nucleus (naturally), and the creation of a new element. And because the proton had become a neutron, the nucleus has the same number of nucleons and a similar atomic weight. In electron capture, a nucleus with "too many" protons will actually "pull in" an electron and take it into its nucleus. This electron will "combine" with a proton, and a neutron will result. This will reduce the number of protons in the nucleus, and the creation of a new element -- just like in positron emission. Links to related questions can be found below.
How does an atom that loses electrons such as in beta decay end up with a different atomic number?
When the number of protons in the nucleus is changed, and an electron or positron created, the atom undergoing decay becomes, in effect, a different element. The number of protons is what determines the elemental status of an atom.In beta decay, a neutron becomes a proton and the nucleus releases an electron and antineutrino.In beta+ decay (aka positron emission), a proton becomes a neutron, releasing a positron and antineutrino. In each case, the decay changes the neutron/proton ratio and makes the atom more stable.
What will happen to an atom is an beta particles emits or adds?
The beta particle will alter the electromagnetic field of the atom. An electron will add to the electromagnetic charge if emitted, and subtract from, if it is absorbed. A positron will do the opposite. The atomic nucleus will also change. an electron can convert a neutron to a proton if emitted, and a proton to a neutron if absorbed. The positron, again, will do the opposite.
IS POSITRON IS NUCLEON?
No, a positron is not a nucleon.The term nucleon is applied to one of the two constituent particles that make up the nucleus of an atom. Those are the proton and the neutron, which are baryons.Whereas, positrons is a subatomic particle having the same mass as an electron but with an electric charge of +1 (an electron has a charge of −1).It constitutes the antiparticle of an electron. We don't see antimatter particles of any kind hanging around long in our "reality" here. (They "combine" with their antiparticles, and mutual annihilation will occur.)Should we investigate an antimatter universe, the positron will orbit the nucleus of an antimatter atom, just like the electron does in the atoms we look at. Naturally the nucleus of an antimatter atom will be composed of anti-protons and anti-neutrons.
What is the center of an atom called?
The center of an atom is called a nucleus (nucleifor plural).Center of an atom is called the "Nucleus".
What is the dense center of the atom called?
the denser part of an atom is the nucleus. about 99% of the mass of an atom is concentrated within the atom.
How do positron emission and electron capture change an atom?
After positron emission or electron capture the atomic number is decreased with one.
When bismuth 214 emits a positron the remaining daughter nucleus is what?
lead
