Chapter 2.4, Problem 2.4.2SR

Interpretation Introduction

Interpretation: The unstable isotope to be identified.

Concept Introduction:

Density: the density of the substance is calculated using the formula:

$\text{density = }\frac{\text{mass}}{\text{volume}}$

Atoms: Atoms consist of tiny particles called protons, neutrons and electrons. Proton and neutrons are present in the nucleus and the electron resides around the nucleus. The protons number will be same as the electrons count in the atom.

$\begin{array}{l}{\text{The element symbol : }}_{\text{Z}}^{\text{A}}\text{X,}\\ \text{where, A (mass number) = no}\text{.of protons + no}\text{.of neutrons}\text{.}\\ \text{ Z (atomic number) = no}\text{. of protons}\text{. (electrons = protons)}\text{.}\end{array}$

Nuclear stability: The nucleus is composed of protons and neutrons. The strongest nuclear force binds the particles tightly. Though the protons repel each other due to no attraction between similar charges, possess short-range attractions made the attraction possible between proton and proton, proton and neutron, neutron and neutron.

The stability of any element is determined by the difference between columbic repulsion and the short-range attraction. If repulsion outweighs the attraction, the disintegration of nucleus occurs by producing the daughter nuclides. If the attractive forces prevail, the nucleus is stable.