Fill in the blanks in the following sentences with appropriate words:
During the emission of a beta particle, the _______ number remains the same.

Explanation

To solve the question, we need to understand the process of beta decay and the properties of particles involved.

1. **Understanding Beta Decay**:
- Beta decay is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted from an atomic nucleus.
- During this process, a neutron in the nucleus is transformed into a proton (or vice versa), which results in the emission of a beta particle.

2. **Identifying the Mass Number**:
- The mass number of an atom is the total number of protons and neutrons in its nucleus.
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