Answer: There are 8 protons in oxygen-18 and 36 neutrons in copper-65.
Explanation:
An atom contains three sub-atomic particles, that is, protons, neutrons and electrons.
The atomic number is the total number of protons present in an atom. For oxygen-18, the atomic mass is 18.
Atomic mass is the sum of total number of protons and electrons present in an atom. As the atomic number of an oxygen atom is 8 so the number of protons present in oxygen-18 is 8.
The atomic mass of copper is 65 and for a copper atom, the atomic number is 29. Hence, the number of neutrons for copper-65 is as follows.
Atomic mass = no. of protons + no. of neutrons
65 = 29 + no. of neutrons
no. of neutrons = 65 - 29 = 36
Thus, we can conclude that there are 8 protons in oxygen-18 and 36 neutrons in copper-65.
