Question
Question: Charge on a positron is equal to that of ------- (A) Proton (B) Electron (C) Nucleon (D) Neu...
Charge on a positron is equal to that of -------
(A) Proton
(B) Electron
(C) Nucleon
(D) Neutron
Solution
A positive electron is called a positron. A positron is emitted during a nuclear reaction by the release of a proton from the nucleus of a radioactive element. In positron emission, the number of protons decreases by one and the number of neutrons inside the nucleus remains unchanged.
Complete step by step answer:
A positron emission takes place when a proton inside a radioactive nucleus converts into a neutron and releases a positron and an electron neutrino. Because of the conversion of a proton into a neutron, the number of protons in the original element decreases by one, while the number of neutrons remains unchanged by releasing a neutron in the form of an electron neutrino.
As mentioned earlier, a positron is a positive electron, which means that the charge on a positron is equal to that of an electron, but positive in charge, unlike an electron. The charge on an electron is −1.6×10−19 coulomb. So, the charge on a positron will be just the same in magnitude but opposite in charge, i.e, +1.6×10−19 coulomb. The symbol for a positron is 10e.
If we remember, the charge on a proton is also the same in magnitude and opposite in charge of an electron. Therefore, the charge on a proton is +1.6×10−19 coulomb. As we see that the charge on a positron and a proton are identical, it can be said that the charge of a positron is equal to that of a proton.
The following reaction gives an example of a reaction releasing a positron and an electron neutrino (ve):
1223Mg→1123Na+10e+ve.
So, the correct answer is Option A.
Note: Proton – A proton is a positively charged particle present inside the nucleus of an atom with a charge of +1.6×10−19 coulomb.
Electron - An electron is a negatively charged particle present revolving around the nucleus of an atom in circular orbits, having a charge of +1.6×10−19 coulomb.
Nucleon – The total number of protons and neutrons present inside the nucleus of an atom are called nucleons.
Neutron – The neutral particles or the particles with no charge and only mass, present inside the nucleus of an atom are called neutrons.