Question

Question: Many nuclides with atomic numbers greater than \({\rm{83}}\) decay by processes such as electron emission. Explain the observation that the emissions from these unstable nuclides also normally include \({\rm{\alpha }}\) particles.

Short answer

Many nuclides with atomic numbers greater than \({\rm{83}}\) decay by processes such as electron emission, which also normally include \({\rm{\alpha }}\) particles because the newly formed nuclei will be more stable than their parent nuclei.

Step-by-step solution

Introduction

Alpha decay, also known as\({\rm{\alpha - }}\)decay, is a type of radioactive decay in which an atomic nucleus produces an alpha particle (helium nucleus) and converts or 'decays' into a new atomic nucleus with a mass number of four and an atomic number of two.

Emissions from unstable Nuclides

Many nuclides with an atomic number greater than \(83\) decay by a process like the emission of an alpha particle because if the alpha particle is emitted, the newly formed nuclei (we can call them daughter nuclei) will be closer to the band of stability, which can be seen in the below figure:

That means that daughter nuclei will be more stable than their parent nuclei in the case of alpha particle emission.

Therefore, the decay of the nuclides involves\({\rm{\alpha }}\)particles which makes the newly formed nuclei more stable.