Which type of particle retains the identity of an element during a chemical type reaction?
The identity of an element depends on the number of protons of that element.
Assuming all elements are made up of atoms...
If you change the number protons on an atom, you change the atom of an atom's identity.
If you change the number electrons on an atom, you changed the atom to an ion.
If you change the number of neutrons, you changed the atom to an isotope of an element.