Chapter 25, Problem 1STP

Interpretation Introduction

Interpretation:

Changes are determined in the radioisotope when it undergoes beta emission.

Concept interpretation:

When the ratio of neutrons to protons in the nucleus is much high, then beta emission takes place.

Answer to Problem 1STP

When a radioisotope undergoes beta emission, the atomic number increases.

Explanation of Solution

In the beta emission process, the neutron from the nucleus of the isotope breaks apart into a proton that stays in the nucleus, and also a fast-moving electron that is released. This can be represented as follows:

  $\text{n}\to \text{P}\text{+}\text{e}$

The beta particle that is emitted in this radioactive decay is the beta particle.

Since the beta particle’s electron has no mass (the mass number is zero) and has a -1 charge, we can conclude that when the radioisotope undergoes beta emission, its mass number stays the same, but its atomic number increases.