The atomic number of an atom is determined by the number of protons it contains. Therefore, if an atom has 8 protons, its atomic number would be 8.
The mass number of an atom is the sum of its protons and neutrons. In this case, the atom has 8 protons and 10 neutrons, so its mass number would be:
Mass number = Number of protons + Number of neutrons Mass number = 8 protons + 10 neutrons Mass number = 18
So, the atom with 10 electrons, 8 protons, and 10 neutrons has an atomic number of 8 and a mass number of 18.