Chapter 10, Problem 10.9E

(a)

Interpretation Introduction

Interpretation:

The balanced nuclear reaction for the beta decay of boron -12 has to be given.

Concept Introduction:

Neutron-capture reaction:

Neutron capture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus.  Since neutrons have no electric charge, they can enter a nucleus more easily than positively charged protons which are repelled electro statically.

Beta decay reaction:

Beta particles are electrons (electrons with positive electric charge).  Beta decay occurs when in a nucleus with too many protons or too many neutrons, one of the protons or neutrons is transformed into the other.

  ${}_{\text{Z}}{\text{X}}^{\text{A}}{\stackrel{}{\to }}_{\text{Z+1}}{\text{X}}^{\text{A}}{\text{+}}_{\text{-1}}{\text{e}}^{\text{0}}$

(b)

Interpretation Introduction

Interpretation:

The particle which 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 ${}_{\text{6}}{\text{C}}^{\text{14}}$ 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.

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