The atomic mass
of an element is a weighted average of the masses of its isotopes and
calculated in accordance to the relative abundances of the isotopes 5 A nucleus can be considered to be spherical in shape and assigned a
radius Electron scattering experiments allow determination of the
nuclear radius; it is found that radii of nuclei fit the formula
R = R0 A1/3,
where R0 = a constant = 1