Which subatomic particle determines the identity of an atom?

The central, dense part of an atom that contains most of the mass. An atom that has the same number of protons but a different number of neutrons. Which subatomic particle determines the identity of an element? Which subatomic particle determines the isotope of an element? read more

Protons. By definition: Atomic number is equal to the number of protons in the element's atom. read more

A neutron is shot at a large atom, which absorbs the neutron, which makes it unstable, and so it splits into smaller atoms, releasing energy and more neutrons, which go on to split more atoms. It's a chain reaction. read more