How to find the Number of Protons, Electrons, Neutrons for Chlorine (Cl)
Aug 27, 2019 — How many protons, neutrons, and electrons are in the atom … the atomic number from the mass number gives us 20 neutrons (37-17=20).1 answer · Top answer: In a neutral Cl atom, there are 17 Protons and electrons. Subtracting the atomic number from the mass number gives us 20 neutrons (37-17=20).