what is the number at the end of an isotopes name?\natomic number\nneutron number\nmass number\nelectron…

Brief Explanations:

Isotopes are atoms of the same element with the same atomic number (same number of protons) but different mass numbers (different number of neutrons). The name of an isotope is written as the element name followed by the mass number. For example, carbon - 14 has a mass number of 14. The atomic number is the number of protons, the neutron number is (n=\text{Mass number}-\text{Atomic number}), and the electron number (in a neutral atom) is equal to the atomic number.

Answer:

mass number