Question

The radius of oxygen nucleus ${(}_8{O}^{16})$ is $2.8\times {10}^{-15}$m. Calculate the radius of the lead nucleus.

Answer 1

$\because R=R_o(A{)}^{1/3}$

where $R_o$ is constant and $A$ is mass number

For ${}_8{O}^{16}=2.8\times {10}^{-15}=R_o\times (16{)}^{1/3}{R}_o=\frac{2.8\times {10}^{-15}}{2.51}=1.11\times {10}^{-15}m$

For ${}_{82}P{b}^{207}\Rightarrow$$R=R_o(A{)}^{1/3}=R=1.11\times {10}^{-15}\times (207{)}^{1/3}=6.56\times {10}^{-15}m$