Question

During the emission of a beta particle, the ________number remains the same.
A) atomic
B) mass
C) neutron
D) none of the above

Answer 1

Hint: From the question, the emission of beta particles, atomic number of the particle is increased or decreased it is depending on the balance of proton and neutron. Depending on the changes of proton and neutron mass numbers would vary.

Complete step by step solution:
In beta decay number, the mass number of the beta particle remains unchanged which means it should be the same. But, in the beta decay number, the atomic number of the particle changes by $1$. In beta decay number either the neutron decays into the proton or the proton decays into the neutron. In the beta decay number, the mass number would be the same.
In beta decay, the process of radioactive disintegration by which some atomic nuclei spontaneously dissipate the excess amount of energy and it undergoes a change of positive amount of energy without any change in mass number of the beta particle.
Here, we know that the emission of a beta particle, the mass number remains the same.

Hence from the above option, option B is correct.

Note: From the question we know that the beta particle atomic number changes. But compared to gamma or alpha decay, beta decay is a relatively slow process. Because beta decay allows the nucleus to the proton and the neutron. When they have a lot of neutrons compared to the protons negative beta decay takes place. But here the proton and neutrons are equal so the atomic number is changed.