Question

When a beta minus decay occurs in an unstable nucleus, what happens to the atomic number of the nucleus?The atomic number increases by 1.The atomic number decreases by 1.The atomic number remains constant.The atomic number increases by 2.The atomic number decreases by 2.

Answer 1

The atomic number increases by 1.

Step-by-step explanation:

The beta minus decay is a process in which a neutron decays into a proton, emitting an electron and an anti-neutrino:

`n \rightarrow p + e + \bar{\\u}`

If this process occurs inside an unstable nucleus, we notice that:

- a neutron is converted into a proton, therefore

- the number of neutrons decreases by 1 and the number of protons increases by 1

Keep in mind that the atomic number of a nucleus corresponds to the number of protons it contains: therefore, since this number increases by 1, then the atomic number increases by 1.