Chapter 24, Problem 41A

Interpretation Introduction

Interpretation:

The element to which promethium changes in the given process needs to be explained.

Concept introduction:

Isotopes of atoms with unstable nuclei are called radioisotopes. Such unstable nuclei emit radiation to create more stable atomic structures through a mechanism called radioactive decay. Unstable atoms lose energy during radioactive decay by releasing radiation. Three types of radiation are alpha $\left(\text{α}\right)$, beta $\left(\text{β}\right)\text{,}$ and gamma $\left(\text{γ}\right)$.

Answer to Problem 41A

Promethium changes into samarium.

Explanation of Solution

Any radioisotope which undergoes beta decay increases its atomic number by one and mass number remains same. As a result of beta decay an unstable nucleus receives a proton and emits beta particles.

Beta decay of promethium-147 produces samarium-147. In this decay, the mass number of both promethiumand samarium remains same and atomic number is increases by one.

$\text{P}\text{m}\to \text{S}\text{m}+\text{β}$

Conclusion

The result of beta decay is that an unstable nucleus gains a proton and emits an electron.