The isotopes of an element differ in the number or neutrons whereas the number of protons or electrons of a neutral atom stays the same. The molar mass of the element is based on the percent abundances of different isotopes and the individual molar mass of each isotope.
Answer:
1..... nucleus
2......electron cloud
3.......protons
4........Neutrons
5..........electron
6............electrons
7...............Isotopes
8.....,...........ions
9....................charge