Question

How does the nucleus change in beta-plus decay?(1 point)
Responses

The mass number remains the same, and the atomic number decreases by one.
The mass number remains the same, and the atomic number decreases by one.

The mass number decreases by one, and the atomic number remains the same.
The mass number decreases by one, and the atomic number remains the same.

The mass number remains the same, and the atomic number increases by one.
The mass number remains the same, and the atomic number increases by one.

The mass number increases by one, and the atomic number remains the same.
The mass number increases by one, and the atomic number remains the same.

Answer 1

In beta-plus decay (or positron emission), a proton in the nucleus is transformed into a neutron, and a positron (the antimatter counterpart of an electron) is emitted.

As a result:

- The mass number remains the same, because the total number of nucleons (protons + neutrons) does not change.
- The atomic number decreases by one, as the nucleus loses a proton.

Therefore, the correct response is:

**The mass number remains the same, and the atomic number decreases by one.**