In the thorium decay series, thorium-$232$ loses a total of six $\alpha$ particles and four $\beta$ particles in a $10$-stage process. What is the final isotope produced?

Why is it preferable to use nuclear binding energy per nucleon for a comparison of the stabilities of different nuclei?

How does Einstein's equation, $E=m c^2$, enable us to calculate nuclear binding energy?

The following radioactive isotopes are used in medicine for imaging organs, studying blood circulation, treating cancer, and so on. Give the number of neutrons present in each isotope:

$$^{198}\mathrm{Au}$$

$$^{47}\mathrm{Ca}$$

$$^{60}\mathrm{Co}$$

$$^{18}\mathrm{F}$$

$$^{125}\mathrm{I}$$

$$^{131}\mathrm{I}$$

$$^{42}\mathrm{K}$$

$$^{43}\mathrm{K}$$

$$^{24}\mathrm{Na}$$

$$^{32}\mathrm{P}$$

$$^{85}\mathrm{Sr}$$

$$^{99}\mathrm{Tc}$$

Define nuclear binding energy, mass defect, and nucleon.