Chapter 10, Problem 10.10E

(a)

Interpretation Introduction

Interpretation:

The balanced nuclear reaction for the alpha decay of actinium-225 has to be given.

Concept Introduction:

Alpha decay reaction:

Alpha decay or $\text{ α}$-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms into a different atomic nucleus with a mass number that is reduced by four and an atomic number that is reduced by two.

  ${{}_{\text{Z}}}^{\text{A}}\text{X}{\stackrel{}{\to }}_{\text{Z-2}}{}^{\text{A-4}}{\text{X+}}_{\text{2}}{}^{\text{4}}\text{He}$

(b)

Interpretation Introduction

Interpretation:

The particle that is closer to the band of stability has to be given.

Concept Introduction:

Neutron-rich nuclei are nuclei with a high proportion of neutrons.  These nuclei tend to decay in such a way that the final $\text{n/p}$ ratio is closer to that found in the band of stability (black line).  For example, a ${{}_{\text{6}}}^{\text{14}}\text{C}$ nucleus can reach a lower energy by ejecting alpha particle which reduces the n/p ratio as a result of the conversion of a neutron into a proton.

  ${{}_{\text{6}}}^{\text{14}}\text{C}{\stackrel{}{\to }}_{\text{7}}{}^{\text{14}}{\text{N+}}_{\text{1}}{}^{\text{0}}\text{e}$