The ratio between protons and neutrons is very important.
The stability of an atom is determined by the:
The physical size of an atom is largely determined by the size of the electron cloud.
By the size of the atom and its mass
The atomic number of an atom is determined by the number of protons it has.
The number of protons in the nucleus of the atom.
By the atomic mass
Different isotopes of an atom are determined by the number of neutrons it contains.
Atomic number.
Electron Configuration
The Atomic Number
No because they are the furthest from the nucleus.
Atomic mass.