What is the change on the subatomic particles represented in Figure 4-3? Assuming all the particles in the nucleus are visible, what are the atomic and mass numbers of the atom shown?

Explanation:
Atomic number means the number of protons an atom holds. Whereas mass number equals (number of protons + number of neutrons).
The given figure shows that there are 9 neutrons and 8 protons.
Therefore,
mass number of the atom = number of protons + number of neutrons
= 8 + 9
= 17
Hence, mass number of the atom is 17 and atomic number of the atom is 8.