The central core of the atom which contain all of the atom’s +ve charge and most of its mass (more than 99.9%) is known as atomic nucleus. To form a nucleus, protons and neutrons are bound together by the nuclear force.
The dimension of nucleus are much smaller than those at an atom . From particle scattering the radius of an nucleus was
time smaller than the radius of an atom. i.e the volume of a nucleus is about
times the volume of the atom.
In this chapter we shall discuss various properties of nuclei such as their size, mass and stability and also associated nuclear phenomena such as radioactivity, fission and fusion.