Question

The name of the isotope is cobalt-60. Find the number of protons, mass number, number of electrons and number of neutrons.

Answer 1

• As the mass number is given as 60 and the element as cobalt, let's write this isotope as ${}_{27}{}^{60}\mathrm{Co}$.
• The atomic number of cobalt is 27 and hence the number of protons=27.
• The number of electrons= atomic number=27.
• Number of neutrons=(mass number-atomic number)=(60-27)=33.

Hence the atomic number=27, number of protons=number of electrons=27, number of neutrons=33.